Polymer alloy and method for manufacturing polymer alloy

ABSTRACT

This invention is a method for manufacturing a polymer alloy, by making at least two resins used as components miscible, and inducing the spinodal decomposition for causing phase separation, for forming a co-continuous structure with a wavelength of concentration fluctuation of 0.001 to 1 μm or a dispersed structure with a distance between particles of 0.001 to 1 μm. This invention is also a polymer alloy manufactured by the method. The polymer alloy of this invention can provide a molded article, film, fibers and the like respectively with excellent mechanical properties at high productivity.

BACKGROUND OF THE INVENTION

[0001] 1. Technical Field

[0002] The present invention relates to a method for manufacturing apolymer alloy having a phase-separated structure consisting of at leasttwo components, polymer alloy pellets, a polymer alloy film or sheet, amolded polymer alloy article, a polymer alloy containing polybutyleneterephthalate resin and a polycarbonate resin, and a polymer alloycontaining polyphenylene sulfide resin and a polyester resin withpolyethylene terephthalate as a main component.

[0003] 2. Background Art

[0004] JP5-156141A describes a molded article having a inter penetratingnetwork structure obtained by melt blending polybutylene terephthalateresin, a polycarbonate resin, and acrylic graft (co)polymer particles.It is disclosed that this structure improves chemicals resistance,strength and toughness to some extent compared with a simple polymeralloy. However, according to the method described in the document,satisfactory effects could not be achieved in improving the strength,toughness and heat resistance of the molded article.

[0005] JP59-58052A discloses a composition consisting of PPS resin and athermoplastic polyester resin, and further teaches a method of mixing anepoxy resin for further enhancing miscibility. However, according to themethod described in the document, it was difficult to control thedispersion size for making it small. In order to obtain a molded articlehaving excellent strength, toughness and heat resistance, a structurewith a smaller dispersion size is desired. Furthermore, if thedispersion size in a polymer alloy is large, there arise such problemsthat in the case where the polymer alloy is used as fibers, the spinningstability during spinning is poor, and that voids are formed duringstretching, to make the fibers fragile. Therefore, a method capable ofcontrolling the structure for making it finer is desired.

[0006] JP8-113829A describes polymer blend fibers having a dispersedstructure with a dispersion size of 0.001 to 0.4 μm formed in the crosssection of each fiber, by melt-spinning a blend of polymers misciblewith each other on the molecular level in a specific temperature range,in its miscible state, into fibers, and, for example, heat-treating thefibers for causing spinodal decomposition or nucleation and growth, tothereby cause phase decomposition. However, according to the methoddescribed in the document, because of the mechanism, in which the fibersobtained by spinning a polymer blend in its miscible state areheat-treated for causing phase separation, there was a limit incontrolling the structure for making it finely dispersed. Furthermore,there was a limit in applicable combinations of polymers, and the formof the polymer blend was also limited to fibers.

[0007] To allow production of a molded article with excellent strength,toughness and heat resistance, a polymer alloy having excellentregularity and a homogeneously dispersed fine structure is demanded. Amethod for manufacturing it is also demanded. Furthermore, amanufacturing method applicable to combinations of immiscible polymers,hence for more general purposes is also demanded.

[0008] The problem to be solved by this invention is to provide apolymer alloy having excellent regularity and excellent mechanicalproperties, useful as a structural material or a functional material andcapable of being controlled to have a structure on the order ofnanometers or on the order of micrometers. It is also intended toprovide a method for manufacturing the polymer alloy.

GIST OF THE INVENTION

[0009] A first version of this invention is a method for manufacturing apolymer alloy, comprising the step of melt blending at least two resinsused as components miscible under such shear flow as caused by the shearrate kept in a range from 100 to 10000 sec⁻¹ and capable of beingseparated into phases under no shear flow, for making the resinsmiscible and subsequently inducing spinodal decomposition to cause phaseseparation, for forming a co-continuous structure with a wavelength ofconcentration fluctuation of 0.001 to 1 μm or a dispersed structure witha distance between particles of 0.001 to 1 μm.

[0010] A second version of this invention is polymer alloy pellets,comprising at least two resins contained as components immiscible underno shear flow, wherein the said at least two resins contained ascomponents are made miscible.

[0011] A third version of this invention is polymer alloy pellets,comprising at least two resins contained as components, wherein the atleast two resin phases contained as components form a co-continuousstructure with a wavelength of concentration fluctuation of 0.001 to 1μm or a dispersed structure with a distance between particles of 0.001to 1 μm.

[0012] A fourth version of this invention is a polymer alloy film orsheet, comprising at least two resins contained as components, whereinthe at least two resins contained as components form a co-continuousstructure with a wavelength of concentration fluctuation of 0.001 to 1μm or a dispersed structure with a distance between particles of 0.001to 1 μm.

[0013] A fifth version of this invention is a molded polymer alloyarticle, comprising at least two resins contained as components, whereinthe at least two resins contained as components form a co-continuousstructure with a wavelength of concentration fluctuation of 0.001 to 1μm or a dispersed structure with a distance between particles of 0.001to 1 μm.

[0014] A sixth version of this invention is a polymer alloy, comprisingpolybutylene terephthalate and a polycarbonate, and forming aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 1 μm or a dispersed structure with a distance betweenparticles of 0.001 to 1 μm.

[0015] A seventh version of this invention is a polymer alloy,comprising polyphenylene sulfide resin and a polyester resin withpolyethylene terephthalate as a main component, and forming aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 2 μm or a dispersed structure with a distance betweenparticles of 0.001 to 2 μm.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 is a transmission electron microscope photograph showing astructure obtained in the early stage of spinodal decomposition ofWorking Example 2.

[0017]FIG. 2 is a transmission electron microscope photograph showing astructure obtained by coarsening the co-continuous phase formed in theearly stage of spinodal decomposition of Working Example 2.

DESIRABLE MODES FOR CARRYING OUT THE INVENTION

[0018] The first version of this invention is a method for manufacturinga polymer alloy, comprising the step of melt blending at least tworesins used as components miscible under such shear flow as caused bythe shear rate kept in a range from 100 to 10000 sec⁻¹ and capable ofbeing separated into phases under no shear flow, for making the resinsmiscible and subsequently inducing spinodal decomposition to cause phaseseparation, for forming a co-continuous structure with a wavelength ofconcentration fluctuation of 0.001 to 1 μm or a dispersed structure witha distance between particles of 0.001 to 1 μm.

[0019] In general, a polymer alloy consisting of two resins contained ascomponents can have a miscible system, immiscible system or partiallymiscible system. A miscible system refers to a system in which thecomponents are miscible under no shear flow, that is, in an equilibriumstate in the entire practical temperature range from the glasstransition temperature to the thermal decomposition temperature. Animmiscible system refers to a system in which the components areimmiscible in the entire temperature range, contrary to the misciblesystem. A partially miscible system refers to a system in which thecomponents are miscible in a specific range of temperatures and in aspecific range of composition ratios but is immiscible in the otherranges. Furthermore, in reference to the condition for causing phaseseparation, the partially miscible system can be either a system inwhich spinodal decomposition causes phase separation or a system inwhich nucleation and growth cause phase separation.

[0020] Moreover, in the case of a polymer alloy consisting of three ormore components, there can occur a system in which all the three or morecomponents are miscible, a system in which all the three or morecomponents are immiscible, a system in which a miscible mode consistingof two or more components and a mode consisting of the remaining one ormore components are immiscible, a system in which two components form apartially miscible mode while the remaining components are distributedin the partially miscible mode consisting of the two components, etc. Inthis invention, in the case of a polymer alloy consisting of three ormore components, a system in which two components form an immisciblemode while the remaining components are distributed in the immisciblemode consisting of the two components is preferred. In this case, thestructure of the polymer alloy is equivalent to the structure of animmiscible system consisting of two components. The followingdescription is made in reference to a polymer alloy consisting of tworesins contained as components.

[0021] Since the polymer alloy of this invention is immiscible under noshear flow, that is, in an equilibrium state, it belongs to a polymeralloy of an immiscible system in the above-mentioned classification.Even in an immiscible system, melt blending can induce spinodaldecomposition. The polymer alloy of this invention is once made miscibleunder such shear flow as caused by the shear rate kept in a range from100 to 10000 sec⁻¹ during melt blending, that is, in a non-equilibriumstate, and is placed under no shear flow, to cause phase decomposition.So, it is a polymer alloy causing phase separation owing to theso-called shear induced spinodal decomposition.

[0022] The basic portion of the shear induced spinodal decompositionmode of this invention is the same as the spinodal decomposition in theabove-mentioned general partially miscible system. Therefore, thefollowing describes the spinodal decomposition in a general partiallymiscible system and subsequently additionally describes the portionpeculiar to this invention.

[0023] In general, the phase separation caused by the spinodaldecomposition refers to the phase separation caused in the unstablestate inside the spinodal curve in a phase diagram showing the relationbetween the composition ratio of two different resins contained ascomponents and the temperature. On the other hand, the phase separationcaused by nucleation and growth refers to the phase separation caused inthe metastable state inside the binodal curve and outside the spinodalcurve in the phase diagram.

[0024] The spinodal curve refers to the curve drawn in the relationbetween the composition ratio and the temperature, at which curve theresult (∂²ΔGmix/∂φ²) obtained by twice partially differentiating thedifference (ΔGmix) between the free energy in the case where twodifferent resins mixed as components are miscible, and the total of thefree energies in immiscible two phases, with respect to theconcentration (φ), is 0. Inside the spinodal curve, an unstable state of∂²ΔGmix/∂φ²<0 occurs, and outside the spinodal curve, ∂²ΔGmix/∂φ²>0occurs.

[0025] The binodal curve refers to the curve at the boundary between amiscible system region and an immiscible system region in the relationbetween the composition ratio and the temperature.

[0026] A miscible state refers to a state where the components arehomogeneously mixed on the molecular level. Particularly, it refers to acase where a mode consisting of different components does not formstructure of 0.001 μm or more. Furthermore, an immiscible state refersto a case other than the miscible state. That is, it refers to a statewhere a mode consisting of different components forms structure of 0.001μm or more. In this case, structure of 0.001 μm or more refers to aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 1 μm, or a dispersed structure with a distance betweenparticles of 0.001 to 1 μm, etc. Being miscible or not can be judgedusing an electron microscope or differential scanning calorimeter (DSC)or any of various other methods, for example, as described in “PolymerAlloys and Blends, Leszek A. Utracki, Hanser Publishers, Munich ViemaNew York, P. 64.”

[0027] According to the detailed theory, in spinodal decomposition, inthe case where the temperature of a mixture system made homogeneouslymiscible once at a temperature of a miscible range is suddenly changedto a temperature of an unstable range, the system quickly initiatesphase separation toward an equilibrium concentration. In this case, theconcentration is made monochromatic into a certain wavelength, and aco-continuous structure in which both the separated phases arecontinuously and regularly entangled with each other at a wavelength ofconcentration fluctuation (Λm), is formed. After this co-continuousstructure is formed, while the wavelength of concentration fluctuationis kept constant, only the difference between the concentrations of boththe phases increases. This stage is called the early stage of spinodaldecomposition.

[0028] The wavelength of concentration fluctuation (Λm) in theabove-mentioned early stage of spinodal decomposition hasthermodynamically the following relation.

Λm˜[|Ts−T|/Ts]^(−1/2)

[0029] (where Ts is the temperature on the spinodal curve)

[0030] The co-continuous structure refers to a structure in which boththe resins mixed as components form continuous phases respectively andare three-dimensionally entangled with each other. A typical view of theco-continuous structure is described, for example, in “Polymer Alloys:Foundation and Applications (second edition) (Chapter 10.1) (inJapanese)” (Edited by the Society of Polymer Science, Japan: TokyoKagaku Dojin).

[0031] In the shear induced spinodal decomposition of this invention,the application of shear flow expands the miscible region. That is,since the spinodal curve is greatly changed due to the application ofshear flow, the quench depth (|Ts−T|) becomes large even if thetemperature change is equal, compared with the above-mentioned generalspinodal decomposition in which the spinodal curve does not change. As aresult, the wavelength of concentration fluctuation in the early stageof spinodal decomposition in the aforesaid formula can be easilyshortened.

[0032] The method for controlling the wavelength of concentrationfluctuation into a preferred specific value in the early stage is notespecially limited. However, it is preferred to heat-treat at atemperature higher than the lowest temperature of the glass transitiontemperatures of the individual resins contained as the componentsconstituting the polymer alloy and at a temperature capable ofshortening the above-mentioned thermodynamically specified wavelength ofconcentration fluctuation. The glass transition temperature can beobtained from the inflection point identified during heating from roomtemperature at a heating rate of 20° C./min using a differentialscanning calorimeter (DSC).

[0033] The temperature for making miscible, the temperature for inducingspinodal decomposition and other conditions depend on the combination ofthe resins and cannot be generally specified. However, these conditionscan be decided by carrying out simple preliminary experiments based onthe phase diagrams obtained under various shearing conditions.

[0034] The spinodal decomposition that has undergone the early stage asdescribed above reaches the intermediate stage where the increase ofwavelength and the increase of concentration difference occursimultaneously. After the concentration difference has reached theequilibrium concentration, the increase of wavelength occurs as if tofollow autosimilarity in the late stage. After undergoing this stage,the spinodal decomposition progresses till finally the separation intotwo macroscopic phases occurs. In this invention, it is only required tofix the structure in the stage where a desired wavelength ofconcentration fluctuation has been reached before the final separationinto two macroscopic phases. Furthermore, in the process where thewavelength increases from the intermediate stage to the late stage, itcan happen that one phase becomes discontinuous due to the influence ofthe composition ratio or interfacial tension, to change from theaforesaid co-continuous structure to the dispersed structure. In thiscase, it is only required to fix the structure in the stage where adesired distance between particles has been reached.

[0035] The dispersed structure refers to a so-called sea-isles structurein which particles of one phase are dispersed in a matrix of the othercontinuous phase.

[0036] If is preferred to control the wavelength of concentrationfluctuation in the early stage of spinodal decomposition into a rangefrom 0.001 to 0.1 μm, since it is easy to control the structure into aco-continuous structure with the wavelength of concentration fluctuationkept in a range from 0.001 to 1 μm or into a dispersed structure withthe distance between particles kept in a range from 0.001 to 1 μm, evenif the wavelength and concentration difference increase in theabove-mentioned intermediate and subsequent stages. Furthermore, as thefinal structure, a co-continuous structure with the wavelength ofconcentration fluctuation kept in a range from 0.01 to 0.5 μm or adispersed structure with the distance between particles kept in a rangefrom 0.01 to 0.5 μm is preferred for obtaining more excellent mechanicalproperties. Still furthermore, a co-continuous structure with thewavelength of concentration fluctuation kept in a range from 0.01 to 0.3μm or a dispersed structure with the distance between particles kept ina range from 0.01 to 0.3 μm is more preferred.

[0037] The method for coarsening from the early stage is not especiallylimited. However, a method of heat-treating at a temperature higher thanthe lowest temperature among the glass transition temperatures of theindividual resins contained as components constituting the polymer alloycan be preferably used. Furthermore, in the case where the polymer alloyhas a single glass transition temperature in its miscible state or inthe case where the glass transition temperature of the polymer alloy isbetween the glass transition temperatures of the individual resinscontained as the components constituting the polymer alloy in a statewhere phase separation progresses, it is more preferred to heat-treat ata temperature higher than the lowest temperature among the glasstransition temperatures in the polymer alloy. Moreover, in the casewhere one of the individual resins used as the components constitutingthe polymer alloy is a crystalline resin, it is preferred that the heattreatment temperature is higher than the crystal melting temperature ofthe crystalline resin, since the coarsening by the heat treatment can beeffectively achieved. Moreover, it is preferred that the heat treatmenttemperature is within ±20° C. of the crystal melting temperature of thecrystalline resin, since the coarsening can be easily controlled. It ismore preferred that the heat treatment temperature is within ±10° C. ofthe crystal melting temperature. In the case where two or more of theresins used as the components are crystalline resins, it is preferredthe heat treatment temperature is within ±20° C. of the highest crystalmelting temperature among the crystal melting temperatures of thecrystalline resins. It is more preferred that the heat treatmenttemperature is within ±10° C. of the highest crystal meltingtemperature.

[0038] The method for fixing the structure formed by the spinodaldecomposition can be a method of fixing the structure(s) of either orboth of the separated phases by quick cooling or the like. In the casewhere one of the components is thermosetting, a method of using thephenomenon that the phase formed by the thermosetting components cannotmove freely after completion of a reaction can be used. In the casewhere one of the components is a crystalline resin, a method of usingthe phenomenon that the crystalline resin phase cannot move freely aftercrystallization can be used. Among them, in the case where a crystallineresin is used, a method of fixing the structure by means ofcrystallization can be preferably used.

[0039] On the other hand, in a system where nucleation and growth causephase separation, a dispersed structure is formed as a sea-islesstructure already in the early stage, and it grows. So, it is difficultto form a regularly arranged co-continuous structure with the wavelengthof concentration fluctuation kept in a range from 0.001 to 1 μm or aregularly arranged dispersed structure with the distance betweenparticles kept in a range from 0.001 to 1 μm as in this invention.

[0040] To confirm that the co-continuous structure or dispersedstructure of this invention has been obtained, it is important toconfirm a regular periodical structure. For this purpose, for example,the structure is observed with an optical microscope or transmissionelectron microscope, to confirm that a co-continuous structure isformed, and in addition, a light scattering instrument or small-angleX-ray scattering instrument is used for scattering measurement toconfirm that a scattering maximum appears. The optimum measuring rangesof light scattering instruments and small-angle X-ray scatteringinstruments are different from instrument to instrument. So, aninstrument with a measuring range suitable for the wavelength ofconcentration fluctuation should be selected. The existence of ascattering maximum in scattering measurement proves that a regularlyphase-separated structure with a certain wavelength exists. Thewavelength Λm corresponds to the wavelength of concentration fluctuationin the case of co-continuous structure, and corresponds to the distancebetween particles in the case of dispersed structure. The value can becalculated using the wavelength λ of scattered light in a scatteringbody and the scattering angle θm giving the scattering maximum from thefollowing formula:

Λm=(λ/2)/sin(θm/2)

[0041] To induce the spinodal decomposition, it is necessary to oncemake the two or more resins contained as components miscible and then toarrive at the unstable state inside the spinodal curve. In the spinodaldecomposition in a general partially miscible system, if the temperatureis quickly changed to an immiscible range after melt blending in amiscible condition, the spinodal decomposition can be induced. On theother hand, in the shear induced spinodal decomposition of thisinvention, since the resins are made miscible under such shear flow ascaused by the shear rate kept in a range from 100 to 10000 sec⁻¹ duringmelt blending in an immiscible system, the spinodal decomposition can beinduced merely under no shear flow.

[0042] The range of the shear rate must be a range for allowing meltblending. Especially a range from 500 sec⁻¹ to 5000 sec⁻¹ is preferred,and a range from 1000 sec⁻¹ to 3000 sec⁻¹ is more preferred.

[0043] For obtaining the shear rate for example using a parallel platestype shear flow applying device, resins molten by heating to apredetermined temperature are placed between parallel discs, and theshear rate can be obtained from ω×r/h, where r is the distance from thecenter, h is the distance between the parallel discs and ω is theangular speed of rotation.

[0044] The melt blending method for keeping the shear rate in this rangeis not especially limited. As a preferred particular manufacturingmethod, the resins are melt blending in the kneading zone of atwin-screw extruder at a high shear stress, to be made miscible. Theshearing condition and temperature condition for making miscible dependon the molecular weights of the resins and cannot be generallyspecified. However, the conditions can be decided by carrying out simplepreliminary experiments based on phase diagrams obtained under variousshearing conditions. To change the shearing condition, it is effectiveto adjust the number of kneading blocks of the extruder or to adjust thescrew rotated speed.

[0045] The combination of resins that can be separated into phases bythe shear-induced spinodal decomposition is a combination of resins thatare immiscible under no shear flow and are miscible under shear flow,allowing the spinodal decomposition to be induced by the change fromshear flow to no shear flow. Particularly, such combinations include,for example, a combination consisting of a polycarbonate (PC) andstyrene-acrylonitrile copolymer, a combination consisting of PC and athermoplastic polyester resin (more particularly, a combinationconsisting of PC and polybutylene terephthalate (PBT), a combinationconsisting of PC and polyethylene terephthalate, and a combinationconsisting of PC and polypropylene terephthalate), a combinationconsisting of polystyrene and polyvinyl methyl ether, a combinationconsisting of polystyrene and polyisoprene, a combination consisting ofpolystyrene and polyphenylmethylsiloxane, a combination consisting ofethylene-vinyl acetate copolymer and chlorinated polyethylene, acombination consisting of poly(butyl acrylate) and chlorinatedpolyethylene, a combination consisting of polymethyl methacrylate andstyrene-acrylonitrile copolymer, a combination consisting ofpolypropylene and high density polyethylene, a combination consisting ofpolypropylene and ethylene-α-olefin copolymer, a combination consistingof polypropylene and ethylene-polypropylene copolymer, a combinationconsisting of polypropylene and styrene-butadiene copolymer, acombination consisting of polypropylene and the hydrogenation product ofstyrene-butadiene copolymer, a combination consisting of PC andstyrene-butadiene copolymer, a combination consisting of PC and thehydrogenation product of styrene-butadiene copolymer, a combinationconsisting of PBT and styrene-butadiene copolymer, a combinationconsisting of PBT and the hydrogenation product of styrene-butadienecopolymer, etc. Among them, a combination consisting of PC andstyrene-acrylonitrile copolymer, a combination consisting of PC and PBT,a combination consisting of polypropylene and high density polyethylene,a combination consisting of polypropylene and an ethylene-α-olefincopolymer, and a combination consisting of polypropylene andethylene-polypropylene copolymer are preferred since they have excellentmechanical properties. Especially a combination consisting of PBT and PCis preferred.

[0046] A thermoplastic polyester resin refers to a saturated polyesterresin synthesized by an esterification reaction from a dibasic acid orany of its ester-formable derivatives and a diol or any of itsderivatives.

[0047] The basic acids and their ester-formable derivatives includearomatic dicarboxylic acids such as terephthalic acid, isophthalic acid,phthalic acid, 2,6-naphthalenedicarboxylic acid,1,5-naphthalenedicarboxylic acid, bis(p-carboxyphenyl)methane,anthracenedicarboxylic acid, 4,4′-diphenyletherdicarboxylic acid, and5-sodiumsulfoisophthalic acid, aliphatic dicarboxylic acids such asadipic acid, sebacic acid, azelaic acid, and dodecanedioic acid,alicyclic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acidand 1,4-cyclohexanedicarboxylic acid, their lower alcohol esters, etc.The diols and their derivatives include aliphatic glycols with 2 to 20carbon atoms such as ethylene glycol, propylene glycol, 1,4-butanediol,neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, decamethylene glycol,cyclohexanedimethanol, and cyclohexanediol, and long-chain glycols witha molecular weight of 400 to 6000 such as polyethylene glycol,poly-1,3-propylene glycol, polytetramethylene glycol, theirester-formable derivatives, etc.

[0048] Preferred examples of these polymers and copolymers includepolybutylene terephthalate, polybutylene(terephthalate/isophthalate),polybutylene(terephthalate/adipate),polybutylene(terephthalate/sebacate),polybutylene(terephthalate/decanedicarboxylate), polybutylenenaphthalate, polyethylene terephthalate,polyethylene(terephthalate/isophthalate),polyethylene(terephthalate/adipate),polyethylene(terephthalate/5-sodiumsulfoisophthalate),polybutylene(terephthalate/5-sodiumsulfoisophthalate), polyethylenenaphthalate, polycyclohexanedimethylene terephthalate, polypropyleneterephthalate, etc. Among them, polybutylene terephthalate,polybutylene(terephthalate/adipate),polybutylene(terephthalate/decanedicarboxylate), polybutylenenaphthalate, polyethylene terephthalate,polyethylene(terephthalate/adipate), polyethylene naphthalate,polycyclohexanedimethylene terephthalate, and polypropyleneterephthalate are especially preferred. The most preferred ispolybutylene terephthalate.

[0049] Among these polymers and copolymers, a polymer or copolymer withan intrinsic viscosity of 0.36 to 1.60 as measured at 25° C. usingo-chlorophenol solution is preferred in view of moldability andmechanical properties. A polymer or copolymer with its intrinsicviscosity of 0.52 to 1.25 is especially preferred and 0.6 to 1.0 is mostpreferred.

[0050] The polycarbonates include those obtained using one or moreselected from bisphenol A, i.e., 2,2′-bis (4-hydroxyphenyl)propane,4,4′-dihydroxydiphenylalkane, 4,4′dihydroxydiphenylsulfone and4,4′-dihydroxydiphenyl ether as main raw materials. Among them, apolycarbonate produced using bisphenol A, i.e.,2,2′-bis(4-hydroxyphenyl)propane as a main raw material is preferred.Particularly, a polycarbonate obtained by an ester interchange method orphosgene method using, for example, bisphenol A as a dihydroxycomponents is preferred. Furthermore, a compound obtained bysubstituting a part, preferably 10 mol % or less of bisphenol A, forexample, by 4,4′-dihydroxydiphenylalkane, 4,4′-dihdyroxydiphenylsulfone,or 4,4′-dihydroxydiphenyl ether can also be preferably used.

[0051] Furthermore, to the polymer alloy consisting of two resinscontained as components, a third components such as a copolymer, forexample, a block copolymer, graft copolymer or random copolymerrespectively containing the components constituting the polymer alloycan be preferably added, for such reasons that the free energy at theinterface between the separated phases can be lowered and that thewavelength of concentration fluctuation in the co-continuous structureor the distance between particles in the dispersed structure can beeasily controlled. In this case, since the third components such as acopolymer is usually distributed into the respective phases of thepolymer alloy consisting of two resins contained as components excludingthe third components, the polymer alloy obtained can be handled like thepolymer alloy consisting of two resins contained as components.

[0052] The second version of this invention is polymer alloy pellets,comprising at least two resins contained as components immiscible underno shear flow, wherein the said at least two resins contained ascomponents are made miscible.

[0053] In this invention, the polymer alloy immiscible in an equilibriumstate, i.e., under no shear flow is melt blended to be made miscible,and in this state, the structure in the obtained polymer alloy pelletsis fixed.

[0054] In this invention, making miscible refers to a state where thecomponents are homogeneously mixed on the molecular level, particularlyrefers to a case where none of at least two resins contained ascomponents forms phase structure of 0.001 μm or more. This state ofbeing free from the structure can be judged if a very thin section iscut out of a thermoplastic resin pellet and is observed with ahigh-magnification electron microscope.

[0055] The polymer alloy pellets of this invention can be manufacturedby making at least two resins contained as components miscible, forexample, by means of melt blending and quickly cooling them beforeinitiation of spinodal decomposition, for fixing the structure with themiscible state kept as it is. As a particular manufacturing method, theat least two resins contained as components are made miscible by meltblending at a high shear stress in the kneading zone of a twin-screwextruder, and are discharged as a strand that is then quickly cooled inwater, to obtain pellets with the miscible state kept as it is. The highshear stress state can be formed for making the polymer alloy miscibleby using more kneading blocks in the extruder, lowering the resintemperature and enhancing the screw rotated speed. Furthermore, lest thepolymer alloy made miscible should cause spinodal decomposition whenmelt-retained in the retaining portion free from shear stress inside thedie of the extruder, it is preferred that the retention time in the dieis kept short. Moreover, if the temperature of cooling water is keptlow, the molten resin composition can be quickly cooled to fix thestructure with the miscible state kept as it is.

[0056] The shape of the polymer alloy pellets of this invention is notespecially limited, but to allow publicly known plastic processing suchas injection molding or extrusion molding, it is preferred that thepellets have a suitable size and shape. Particular examples arecylinders having a diameter of 1 to 6 mm, preferably 1.5 to 4 mm and alength of 2 to 6 mm, preferably 2.5 to 4 mm and rectangularparallelepipeds having a length and a width of respectively 3 to 6 mmand a thickness of 1.5 to 3 mm.

[0057] As the resins used for the polymer alloy pellets of thisinvention, combinations consisting of resins immiscible under no shearflow and capable of being made miscible by melt blending, as describedfor the first version of this invention, can be preferably used. Amongthem, a combination consisting of a PC resin and a thermoplasticpolyester resin is preferred, and especially a combination consisting ofPC and PBT is preferred.

[0058] It is also preferred that the polymer alloy pellets of thisinvention contain inert particles. The inert particles include polymericcrosslinked particles, alumina particles, spherical silica particles,cohesive silica particles, aluminum silicate particles, calciumcarbonate particles, titanium oxide particles, kaolin particles, etc.Among them, polymeric crosslinked particles, alumina particles,spherical silica particles and aluminum silicate particles can bepreferably used. It is preferred that the average particle size of theinert particles is 0.001 to 5 μm, and a more preferred range is from0.01 to 3 μm. Furthermore, it is preferred that the mixing rate of inertparticles is 0.01 to 10 wt % per 100 wt % of polymer alloy pellets. Amore preferred range is from 0.05 to 5 wt %. An inert particles-mixingrate of less than 0.01 wt % is not preferred, since the sliding propertyduring the molding for producing a film or sheet may be so poor as tolower moldability. On the contrary, an inert particles-mixing rate ofmore than 10 wt % is not preferred either, since the toughness maydecline.

[0059] It is also preferred that the polymer alloy pellets of thisinvention contain a releasing agent. Usable releasing agents include theester compounds obtained from a long-chain aliphatic carboxylic acidsuch as stearic acid or montanic acid and a polyhydric alcohol such asethylene glycol, glycerol or pentaerythritol, amide compounds obtainedfrom a long-chain aliphatic carboxylic acid such as stearic acid ormontanic acid and stearylamine or ethylenediamine, etc., siliconecompounds, etc. Preferred particular examples of the releasing agent areethylene glycol ester and ethylene bisstearylamide of montanic acid,etc.

[0060] It is preferred that the mixing rate of the releasing agent is0.001 to 1 wt % per 100 wt % of polymer alloy pellets, and a morepreferred range is from 0.005 to 0.8 wt %. A releasing agent-mixingrateof less than 0.001 wt % is notpreferred, sincethe releasabilityduring injection molding may become so poor as to lower moldability. Onthe contrary, a releasing agent-mixing rate of more than 1 wt % is notpreferred either, since the releasing agent may bleed out on the surfaceof the molded article to degrade the appearance of the molded article orto contaminate the mold.

[0061] The releasing agent can be entirely contained in the polymeralloy pellets, but it is also preferred that the releasing agent existspartially or entirely on the surfaces of the polymer alloy pellets.

[0062] The polymer alloy pellets of this invention can further containvarious additives to such an extent that the object of this invention isnot impaired. These additives include, for example, reinforcingmaterials such as talc, kaolin, mica, clay, bentonite, sericite, basicmagnesium carbonate, aluminum hydroxide, glass flakes, glass fibers,carbon fibers, asbestos fibers, rock wool, calciumcarbonate, silicasand, wollastonite, bariumsulfate, glass beads and titanium oxide,non-tabular filler, antioxidant (based on phosphorus, sulfur, etc.),ultraviolet light absorber, thermal stabilizer (based on hinderedphenol, etc.), ester interchange reaction inhibitor, lubricant,antioxidant, blocking preventive, colorant such as dye or pigment, flameretarder (based on halogen, phosphorus, etc.), flame retardant auxiliary(antimony compound typified by antimony trioxide, zirconium oxide,molybdenum oxide, etc.), foaming agent, coupling agent (silane couplingagent or titanium coupling agent containing one or more kinds of epoxygroup, amino group, mercapto group, vinyl group and isocyanate group),antimicrobial agent, etc.

[0063] The polymer alloy pellets of this invention can be manufacturedby any desired molding method, and the molded pellets can have a desiredshape. Molding methods include, for example, melt spinning, injectionmolding, extrusion molding, inflation molding, blow molding, etc. Theindividual molding methods are described later in detail.

[0064] The third version of this invention is polymer alloy pellets,comprising at least two resins contained as components, wherein the atleast two resins contained as components form a co-continuous structurewith a wavelength of concentration fluctuation of 0.001 to 1 μm or adispersed structure with a distance between particles of 0.001 to 1 μm.

[0065] The co-continuous structure and the dispersed structure of thisinvention can be confirmed as described for the first version of thisinvention.

[0066] It is necessary that the pellets of this invention have aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 1 μm or a dispersed structure with a distance betweenparticles of 0.001 to 1 μm. It is preferred that the pellets have aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 0.4 μm or a dispersed structure with a distance betweenparticles of 0.001 to 0.4 μm. A wavelength of concentration fluctuationof more than 0.4 μm is not preferred, since the toughness of the moldedarticle obtained by molding the polymer alloy pellets declines.

[0067] As a method for obtaining the co-continuous structure and thedispersed structure, a method of using the phase separation caused byspinodal decomposition is preferred.

[0068] In general, a polymer alloy consisting of two resins contained ascomponents has a miscible system, immiscible system or partiallymiscible system. These systems are the same as those described for thefirst version of this invention.

[0069] As the method for manufacturing the polymer alloy pellets of thisinvention, a method by melt blending is preferred. As a particularmanufacturing method, at least two resins used as components can be meltblended at a high shear stress in the kneading zone of a twin-screwextruder, to be made miscible, separated into phases by spinodaldecomposition in the extruder, and discharged as a strand that is thencooled by cooling water, to obtain polymer alloy pellets having a fixedco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 1 μm or a fixed dispersed structure with a distance betweenparticles of 0.001 to 1 μm. If the polymer alloy made miscible can bemelt-retained in the retaining portion free from shear stress in the dieof the extruder, the spinodal decomposition can be initiated. If theretention time in the die is made longer or if the cooling water is madewarmer, for gradually cooling the molten polymer alloy, a time availablefor inducing the early stage of spinodal decomposition can be produced.The retention time in the die can be adjusted if the inside volume ofthe die is changed or if the amount of the resin composition dischargedis changed.

[0070] The shape of the polymer alloy pellets of this invention is notespecially limited, but to allow publicly known plastic processing suchas injection molding or extrusion molding, it is preferred that thepellets have a suitable size and shape. Particular examples arecylinders having a diameter of 1 to 6 mm, preferably 1.5 to 4 mm and alength of 2 to 6 mm, preferably 2.5 to 4 mm and rectangularparallelepipeds having a length and a width of respectively 3 to 6 mmand a thickness of 1.5 to 3 mm.

[0071] The resins used for the polymer alloy pellets of this inventionare not especially limited, and combinations of resins described for thefirst version of this invention can be preferably used. Furthermore, thepolymer alloy pellets of this invention can also contain inertparticles, releasing agent and various other additives, as described forthe second version of this invention. Also as the molding methods forthe polymer alloy pellets of this invention, the methods described forthe second version of this invention can be applied.

[0072] The fourth version of this invention is a polymer alloy film orsheet, comprising at least two resins contained as components, whereinthe at least two resins contained as components form a co-continuousstructure with a wavelength of concentration fluctuation of 0.001 to 1μm or a dispersed structure with a distance between particles of 0.001to 1 μm.

[0073] As the method for obtaining the polymer alloy film or sheet, themethod of using the spinodal decomposition described for the firstversion of this invention is preferred. It is preferred to control thewavelength of concentration fluctuation in a range from 0.001 to 0.1 μmin the early stage of spinodal decomposition, since it is easy tocontrol the structure for securing a co-continuous structure with thewavelength of concentration fluctuation kept in a range from 0.001 to 1μm or a dispersed structure with the distance between particles kept ina range from 0.001 to 1 μm, even if the wavelength and concentrationdifference increase in the above-mentioned intermediate and subsequentstages.

[0074] To induce the spinodal decomposition, it is necessary to make thetwo or more resins contained as components miscible, and then to arriveat the unstable state inside the spinodal curve. The methods for makingthe two or more resins contained as components miscible include asolvent casting method and a melt blending method. A solvent castingmethod refers to a method in which after dissolving into a commonsolvent, the solution is transformed into a film or the like by means ofspray drying, freeze drying, solidification in a non-solvent substanceor solvent evaporation. A melt blending method refers to a method inwhich resins of a partially miscible system or an immiscible system aremelt blended, to be made miscible. Among them, a melt blending methodthat is a dry process free from the use of any solvent can bepractically preferably used. As the methods for fixing the structuralproduct achieved by spinodal decomposition, the methods described forthe first version of this invention can be used.

[0075] In the case where at least one of the resins contained as thecomponents constituting the polymer alloy is a crystalline resin, thestructure of the polymer alloy can be easily fixed by crystallizing thecrystalline resin phase, and in addition, when the film or sheet isstretched, the oriented crystallization achieved by the stretchingimproves the mechanical properties. So, it is preferred to use acrystalline resin as at least one of the components.

[0076] The crystalline resin referred to in this invention is notespecially limited, if the resin allows the crystal melting temperatureto be observed by a differential scanning calorimeter (DSC). Forexample, polyester resins, polyamide resins, polyolefins such aspolyethylene, polypropylene, polyvinyl alcohol and polyvinyl chloride,polyoxymethylene and so on can be enumerated.

[0077] As a method for manufacturing the polymer alloy film or sheet, asingle-screw or twin-screw extruder is used to once dissolve at leasttwo resins used as components, and the polymer alloy obtained isdischarged from a T die and cooled for inducing the spinodaldecomposition. Subsequently the structure achieved by the spinodaldecomposition is fixed. More particular methods include a method inwhich the spinodal decomposition induced after discharge is followed bycooling and solidification using a casting drum, for fixing thestructure, a polishing method in which the discharged miscible polymeralloy is formed between two rolls, a calendering method, etc. The methodis not especially limited here. For keeping the molten resins in contactwith a casting drum for casting, such methods as a method of applyingstatic electricity, a method of using an air knife, a method of using aholding drum in opposite to the casting drum can also be used.Furthermore, for casting using a casting drum, it is preferred toinstall the casting drum immediately below the discharge port, for quickcooling. Moreover, it is more preferred to use polymer alloy pelletsmade miscible using a twin-screw extruder before feeding them into anextruder for manufacturing a film or sheet.

[0078] In the case where a polymer alloy of an immiscible system isused, it is possible to use the phase separation caused by the so-calledshear induced spinodal decomposition as described for the first versionof this invention, in which the polymer alloy is melt blended under highshear flow for being made miscible and separated into phases under noshear flow when it is discharged from a T die.

[0079] The shear induced phase dissolution and phase decomposition of animmiscible system can be more preferably used, since the wavelength ofconcentration fluctuation in the early stage of spinodal decompositioncan be easily shortened compared with that of a partially misciblesystem, as described for the first version of this invention.

[0080] The combinations of resins to be subjected to the aforesaid shearinduced spinodal decomposition are the same as described for the firstversion of this invention, and especially a polymer alloy containing PBTand PC is preferred, since the obtained polymer alloy film or sheet canhave excellent strength and toughness, and also excellent moldability.

[0081] In the case where a polymer alloy of a partially miscible systemis used, the polymer alloy is melt blended to be made miscible underconditions for making the resins of a partially miscible systemmiscible. After discharge, the following method can be used. Usually anatmospheric temperature in a range from 10 to 30° C. is used for coolingto induce the spinodal decomposition, and further, a casting drum isused for cooling and solidification, to fix the structure achieved bythe spinodal decomposition. In the case where a polishing method or acalendering method is used, it is desirable to adjust the temperature ofthe rolls used for forming the discharged polymer alloy at thetemperature capable of inducing spinodal decomposition.

[0082] Furthermore, in the case where a polymer alloy of a partiallymiscible system is used, at least two resins contained as componentscapable of being separated into phases by spinodal decomposition areused in combination. Such a system of two components can be realized byselecting a combination consisting of resins small in the difference ofsolubility parameter or using a resin with a low molecular weight as oneof the resins.

[0083] As partially miscible systems, known are a composition with a lowtemperature miscible type phase diagram, which is likely to be mademiscible in a low temperature range, and on the contrary, a compositionwith a high temperature miscible type phase diagram, which is likely tobe made miscible in a high temperature range. The lowest temperatureamong the temperatures demarcating between a miscible zone and animmiscible zone in the low temperature miscible type phase diagram iscalled the lower critical solution temperature (LCST), and the highesttemperature among the temperatures demarcating between a miscible zoneand an immiscible zone in the high temperature miscible type phasediagram is called the upper critical solution temperature (UCST).

[0084] In the case of a low temperature miscible type phase diagram, ifthe two or more resins contained as components made miscible from apartially miscible system are brought to a temperature higher than theLCST and inside the spinodal curve, spinodal decomposition can beinduced. In the case of a high temperature miscible type phase diagram,if they are brought to a temperature lower than the UCST and inside thespinodal curve, spinodal decomposition can be induced. When a film orsheet is formed, it is simpler to induce the spinodal decomposition whenthe resins made miscible in the extruder are discharged to decline intemperature. So, a combination of resins having a low temperaturemiscible type phase diagram is preferred.

[0085] Combinations of resins having the aforesaid low temperaturemiscible type phase diagram include a combination consisting ofpolyvinyl chloride and a poly(n-alkyl methacrylate), a combinationconsisting of polyvinyl chloride and a poly(n-alkyl acrylate), acombination consisting of polyvinylphenol and a poly(n-alkylmethacrylate), a combination consisting of polydimethylsiloxane andpolystyrene, a combination consisting of polyvinylidene fluoride andpoly(methyl methacrylate), a combination consisting of polyvinylidenefluoride and polyvinyl acetate, a combination consisting ofpolyvinylidene fluoride and poly(methyl acrylate) a combinationconsisting of polyvinylidene fluoride and poly(ethyl acrylate), acombination consisting of polyvinyl acetate and poly(methyl acrylate), acombination consisting of polystyrene and polyvinylmethylether, acombination consisting of poly(methyl methacrylate) andstyrene-acrylonitrile copolymer, a combination consisting of poly(methylmethacrylate) and vinylphenol-styrene copolymer, a combinationconsisting of polyvinyl acetate and vinylidenefluoride-hexafluoroacetone copolymer, a combination consisting oftetramethyl polycarbonate and styrene-methyl methacrylate copolymer, acombination consisting of tetramethyl polycarbonate andstyrene-acrylonitrile copolymer, a combination consisting ofpolyvinylphenol and ethylene-methyl methacrylate copolymer, acombination consisting of polyvinylphenol and ethylene-vinyl acetatecopolymer, a combination consisting of poly-ε-caprolactone andstyrene-acrylonitrile copolymer, a combination consisting ofpolyisoprene and butadiene-vinylethylene copolymer, a combinationconsisting of styrene-acrylonitrile copolymer and styrene-maleicanhydride copolymer, a combination consisting of styrene-acrylonitrilecopolymer and styrene-N-phenylmaleimide, a combination consisting ofethylene-vinyl acetate copolymer and vinylidenefluoride-hexafluoroacetone copolymer, etc.

[0086] In the polymer alloy film or sheet obtained by such a method, itis necessary that at least two resins contained as components have aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 1 μm or a dispersed structure with a distance betweenparticles of 0.001 to 1 μm. Furthermore, a co-continuous structure witha wavelength of concentration fluctuation of 0.001 to less than 0.01 μmor a dispersed structure with a distance between particles of 0.001 toless than 0.01 μm is preferred, and a co-continuous structure with awavelength of concentration fluctuation of 0.002 to 0.008 μm or adispersed structure with a distance between particles of 0.002 to 0.008μm is also preferred, since excellent mechanical properties can beobtained. A co-continuous structure with a wavelength of concentrationfluctuation of 0.002 to 0.005 μm or a dispersed structure with adistance between particles of 0.002 to 0.005 μm is more preferred.

[0087] The obtained film can also be stretched. The stretching method isnot especially limited, and either sequential biaxial stretching orsimultaneous biaxial stretching can be used. Often used stretchingratios are in a range from 2 times to 8 times, and often used stretchingspeeds are in a range from 500 to 5000%/min. Furthermore, as for theheat treatment temperature during stretching, a method of heat-treatingat higher than the lowest temperature among the glass transitiontemperatures of the individual resins contained as componentsconstituting the polymer alloy is usually preferably used. In the casewhere the polymer alloy has a single glass transition temperature in itsmiscible state or in the case where the glass transition temperature ofthe polymer alloy is between the glass transition temperatures of theindividual resins used as the components constituting the polymer alloyin a state where phase separation progresses, it is more preferred toheat-treat at a temperature higher than the lowest temperatures amongthe glass transition temperatures in the polymer alloy. Moreover, in thecase where one of the individual resins contained as the componentsconstituting the polymer alloy is a crystalline resin, it is preferredthat the heat treatment temperature is lower than the heatingcrystallization temperature of the crystalline resin, since stretchingis unlikely to be disturbed by the crystallization of the crystallineresin. It is preferred that the stretched film is further heat-treatedfor stabilizing its structure before use. As for the heat treatmenttemperature for stabilization, a method of heat-treating at atemperature higher than the lowest temperature among the glasstransition temperatures of the individual resins contained as thecomponents constituting the polymer alloy is usually preferably used. Inthe case where the glass transition temperature of the polymer alloy isbetween the glass transition temperatures of the individual resinscontained as the components constituting the polymer alloy in a statewhere phase separation progresses, it is more preferred to heat-treat ata temperature higher than the lowest temperature among the glasstransition temperatures in the polymer alloy. Furthermore, the stretchedpolymer alloy film can have a longer wavelength of concentrationfluctuation or a longer distance between particles because of thestretching. It is preferred that at least two resins contained ascomponents in the stretched polymer alloy film have a co-continuousstructure with a wavelength of concentration fluctuation of 0.001 to 1μm or a dispersed structure with a distance between particles of 0.001to 1 μm, since excellent mechanical properties can be obtained.Furthermore, having a co-continuous structure with a wavelength ofconcentration fluctuation of 0.001 to 0.1 μm or a dispersed structurewith a distance between particles of 0.001 to 0.1 μm is preferred inview of the transparency of the film.

[0088] The composition ratio of the resins contained as the componentsconstituting the polymer alloy film or sheet in this invention is notespecially limited, but in the case of two components, usually a rangefrom 95 wt %/5 wt % to 5 wt %/95 wt % can be preferably used, and arange from 90 wt %/10 wt % to 10 wt %/90 wt % can be more preferablyused. Especially a range from 75 wt %/25 wt % to 25 wt %/75 wt % can bepreferably used, since it is relatively easy to obtain the co-continuousstructure.

[0089] Furthermore, to the polymer alloy consisting of two resinscontained as components, a third components such as a copolymer, forexample, a block copolymer, graft copolymer or random copolymerrespectively containing the components constituting the polymer alloycan be preferably added, for such reasons that the free energy at theinterface between the separated phases can be lowered and that thewavelength of concentration fluctuation in the co-continuous structureor the distance between particles in the dispersed structure can beeasily controlled. In this case, since the third components such as acopolymer is usually distributed into the respective phases of thepolymer alloy consisting of two resins contained as components excludingthe third components, the polymer alloy obtained can be handled like thepolymer alloy consisting of two resins contained as components.

[0090] The polymer alloy film or sheet of this invention can containfurther other various additives to such an extent that the object ofthis invention is not impaired. These other additives include, forexample, a lubricant such as inorganic particles and/or crosslinkedorganic particles, antioxidant (based on phosphorus, sulfur, etc.),ultraviolet light absorber, thermal stabilizer (based on hinderedphenol, etc.), releasing agent, antioxidant, blocking preventive,colorant such as dye or pigment, antimicrobial agent, etc.

[0091] These additives can be mixed at any desired stage while thepolymer alloy film or sheet of this invention is manufactured, a methodof producing a master batch by adding these additives to one of theresins constituting the polymer alloy and adding the master batch can beusually preferably used.

[0092] The fifth version of this invention is a molded polymer alloyarticle, comprising at least two resins contained as components, whereinthe at least two resins contained as components form a co-continuousstructure with a wavelength of concentration fluctuation of0.001 to 1 μmor a dispersed structure with a distance between particles of 0.001 to 1μm.

[0093] As the method for obtaining a molded polymer alloy article havingsuch a structure, the method of using the spinodal decompositiondescribed for the first version of this invention is preferred.Furthermore, it is preferred to control the wavelength of concentrationfluctuation in a range from 0.001 to 0.1 μm in the early stage ofspinodal decomposition, since it is easy to control the structure forsecuring a co-continuous structure with the wavelength of concentrationfluctuation kept in a range from 0.001 to 1 μm or a dispersed structurewith the distance between particles kept in a range from 0.001 to 1 μm,even if the wavelength and concentration difference increase in theabove-mentioned intermediate and subsequent stages. Moreover, forobtaining more excellent properties, it is more preferred to control thestructure after coarsening for securing a co-continuous structure withthe wavelength of concentration fluctuation kept in a range from 0.002to 0.5 μm or a dispersed structure with the distance between particleskept in a range from 0.002 to 0.5 μm. It is more preferred to controlthe structure for securing a co-continuous structure with the wavelengthof concentration fluctuation kept in a range from 0.003 to 0.3 μm or adispersed structure with the distance between particles kept in a rangefrom 0.003 to 0.3 μm.

[0094] The method for inducing the spinodal decomposition is the same asdescribed for the fourth version of this invention. In this invention, acombination consisting of polybutylene terephthalate (PBT) and apolycarbonate (PC) can be preferably used, since excellent mechanicalstrength can be obtained. The PBT and PC preferably used in thisinvention are as described for the first version of this invention.

[0095] The amounts of PBT and PC to be mixed are not especially limited,but it is preferred to use 10 to 1000 parts by weight of PC per 100parts by weight of PBT. It is more preferred to use 10 to 100 parts byweight of PC per 100 parts by weight of PBT. For obtaining a molded longarticle or a molded precision article, it is preferred to keep theamount of PC at 100 parts by weight or less, lest the flowability duringinjection molding should decline. A PC amount of less than 10 parts byweight is not preferred, since the effect of improving dimensionalstability declines. In view of the balance between flowability anddimensional stability, it is more preferred to use 20 to 50 parts byweight of PC per 100 parts by weight of PBT.

[0096] The molded polymer alloy article of this invention is a moldedarticle having a three-dimensional structure. The molding method can be,for example, injection molding, extrusion molding, inflation molding, orblow molding, etc. Among them, injection molding can be preferably used,since the structure can be fixed in the mold.

[0097] As a preferred method for manufacturing the molded polymer alloyarticle of this invention, at least two resins used as components areonce made miscible in a twin-screw extruder capable of applying highshear flow, are discharged from the extruder, to be immediately cooled,for producing pellets with their structure fixed in a state where thetwo resins contained as components are kept miscible, or producingpellets having a co-continuous structure with a wavelength ofconcentration fluctuation of 0.4 μm or less in the early stage ofspinodal decomposition. Then, the pellets are injection-molded tofurther inducing spinodal decomposition during injection molding, toproduce a molded polymer alloy article having a co-continuous structurewith a wavelength of concentration fluctuation of 0.001 to 1 μm or adispersed structure with a distance between particles of 0.001 to 1 μm.

[0098] The polymer alloy constituting the molded polymer alloy articleof this invention can contain further various additives to such anextent that the object of this invention is not impaired. Theseadditives include, for example, reinforcing materials such as talc,kaolin, mica, clay, bentonite, sericite, basic magnesium carbonate,aluminum hydroxide, glass flakes, glass fibers, carbon fibers, asbestosfibers, rock wool, calcium carbonate, silica sand, wollastonite, bariumsulfate, glass beads and titanium oxide, non-tabular filler, antioxidant(based on phosphorus, sulfur, etc.), ultraviolet light absorber, thermalstabilizer (based on hindered phenol, etc.), ester interchange reactioninhibitor, lubricant, antioxidant, blocking preventive, colorant such asdye or pigment, flame retarder (based on halogen, phosphorus, etc.),flame retardant auxiliary (antimony compound typified by antimonytrioxide, zirconium oxide, molybdenum oxide, etc.), foaming agent,coupling agent (silane coupling agent or titanium coupling agentcontaining one or more kinds of epoxy group, amino group, mercaptogroup, vinyl group and isocyanate group), antimicrobial agent, etc.

[0099] These additives can be added at any desired stage while themolded polymer alloy article of this invention is manufactured. Forexample, such methods as a method of adding simultaneously when the tworesins used as components are mixed, a method of adding after the tworesins used as components have been melt blended, and a method of addingat first to one of the two resins used as components, melt blending andmixing the other resin can be used.

[0100] Furthermore, the molded polymer alloy article of this inventioncan also contain another thermoplastic resin or thermosetting resin tosuch an extent that the structure of this invention is not impaired. Thethermoplastic resins include, for example, polyethylene, polyamides,polyphenylene sulfide, polyether ether ketone, liquid crystalpolyesters, polyacetal, polysulfones, polyether sulfones, polyphenyleneoxide, etc. The thermosetting resins include, for example, phenolresins, melamine resins, unsaturated polyester resins, silicone resins,epoxy resins, etc.

[0101] The other thermoplastic resin or thermosetting resin can be mixedat any stage while the molded polymer alloy article of this invention ismanufactured. For example, such methods as a method of addingsimultaneously when the two resins used as components are mixed, amethod of adding after the two resins used as components have been meltblended, or a method of adding at first to one of the two resins used ascomponents, melt blending and mixing the other resin can be used.

[0102] The sixth version of this invention is a polymer alloy,comprising polybutylene terephthalate and a polycarbonate, and forming aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 1 μm or a dispersed structure with a distance betweenparticles of 0.001 to 1 μm.

[0103] The PBT and PC preferably used in this invention are the same asdescribed for the first version of this invention.

[0104] The amounts of PBT and PC to be mixed are not especially limited,but it is preferred to use 10 to 1000 parts by weight of PC per 100parts by weight of PBT. It is more preferred to use 10 to 100 parts byweight of PC per 100 parts by weight of PBT.

[0105] The polymer alloy of this invention has a co-continuous structurehaving a specific wavelength of concentration fluctuation or a dispersedstructure with a specific distance between particles.

[0106] The polymer alloy having such a structure can be obtained byusing the phase separation caused by the spinodal decomposition, asdescribed for the first version of this invention. If the wavelength ofconcentration fluctuation in the early stage of spinodal decompositionis controlled in a range from 0.001 to 0.1 μm, the structure can becontrolled to ensure a co-continuous structure with the wavelength ofconcentration fluctuation kept in a range from 0.001 to 1 μm or adispersed structure with the distance between particles kept in a rangefrom 0.001 to 1 μm, even if the wavelength and the concentrationdifference increase in the intermediate and subsequent stages.

[0107] The method for inducing the spinodal decomposition is the same asdescribed for the fourth version of this invention.

[0108] The polymer alloy of this invention can also contain furthervarious additives to such an extent that the object of this invention isnot impaired. These additives include, for example, reinforcingmaterials such as talc, kaolin, mica, clay, bentonite, sericite, basicmagnesium carbonate, aluminum hydroxide, glass flakes, glass fibers,carbon fibers, asbestos fibers, rock wool, calcium carbonate, silicasand, wollastonite, barium sulfate, glass beads and titanium oxide,non-tabular filler, antioxidant (based on phosphorus, sulfur, etc.),ultraviolet light absorber, thermal stabilizer (based on hinderedphenol, etc.), ester interchange reaction inhibitor, lubricant,antioxidant, blocking preventive, colorant such as dye or pigment, flameretarder (based on halogen, phosphorus, etc.), flame retardant auxiliary(antimony compound typified by antimony trioxide, zirconium oxide,molybdenum oxide, etc.), foaming agent, coupling agent (silane couplingagent or titanium coupling agent containing one or more kinds of epoxygroup, amino group, mercapto group, vinyl group and isocyanate group),antimicrobial agent, etc.

[0109] These additives can be added at any desired stage while thepolymer alloy of this invention is manufactured. For example, suchmethods as a method of adding simultaneously when PBT and PC are mixed,a method of adding after PBT and PC have been melt blended, and a methodof adding at first to either PBT or PC resin, melt blending and mixingthe remaining resin can be used.

[0110] The polymer alloy of this invention can further contain anotherthermoplastic resin or thermosetting resin to such an extent that thestructure of this invention is not impaired. The thermoplastic resinsinclude, for example, polyethylene, polyamides, polyphenylene sulfide,polyether ether ketone, liquid crystal polyesters, polyacetal,polysulfones, polyether sulfones, polyphenylene oxide, etc. Thethermosetting resins include, for example, phenol resins, melamineresins, unsaturated polyester resins, silicone resins, epoxy resins,etc.

[0111] The other thermoplastic resin or thermosetting resin can be mixedat any stage while the polymer alloy of this invention is manufactured.For example, such methods as a method of adding simultaneously when PBTand PC are mixed, a method of adding after PBT and PC have been meltblended, or a method of adding at first to either PBT resin or PC resin,melt blending and mixing the remaining resin can be used.

[0112] The polymer alloy obtained in this invention can be molded by anydesired method, for obtaining fibers, film, sheet or molded article,etc. The molding method can be, for example, melt spinning, injectionmolding, extrusion molding, inflation molding or blow molding, etc.

[0113] The seventh version of this invention is a polymer alloy,comprising polyphenylene sulfide resin and a polyester resin withpolyethylene terephthalate as a main component, and forming aco-continuous structure with a wavelength of concentration fluctuationof 0. 001 to 2 μm or a dispersed structure with a distance betweenparticles of 0.001 to 2 μm.

[0114] The polyphenylene sulfide (PPS) used in this invention is apolymer containing the recurring units represented by the followingstructural formula:

[0115] In view of heat resistance, a polymer containing 70 mol % ormore, especially 90 mol % or more of the recurring units represented bythe above structural formula is preferred. The PPS can contain 30 mol %or less of the recurring units represented by any of the followingstructural formulae, etc.

[0116] The PPS used in this invention can be manufactured, for example,by a publicly known ordinary method, such as a method described inJP45-3368B, in which a polymer with a relatively small molecular weightis obtained, or a method as described in JP52-12240B or JP61-7332A, inwhich a polymer with a relatively large molecular weight is obtained. Inthis invention, the PPS obtained as described above can be, for example,heated in air for achieving crosslinking/increasing its molecularweight, or heat-treated in an atmosphere of an inert gas such asnitrogen or under reduced pressure, or washed using an organic solvent,hot water, acid aqueous solution or the like, or activated using afunctional group-containing compound such as a functionalgroup-containing disulfide compound, as any of various treatments to beapplied before use. Two or more of these treatments can of course beapplied. Furthermore, differently treated two or more PPS can also beused as a mixture. Particular methods for using differently treated twoor more PPS as a mixture include mixing PPS crosslinked by heating inair and non-heat-treated PPS, mixing PPS washed using an acid aqueoussolution and PPS washed using an organic solvent, mixing PPS washedusing an organic solvent and PPS not washed using an organic solvent,and so on.

[0117] The molecular weight of the PPS used in this invention is notespecially limited, but should be adequately selected, since it relatesto the conditions for inducing spinodal decomposition described later.Usually PPS of 5 to 1,000 Pa.s (320° C., shear rate 1000 sec⁻¹), andabove all, PPS of 10 to 500 Pa.s can be preferably used.

[0118] A particular method for heating PPS for achievingcrosslinking/increasing its molecular weight is, for example, heating inan atmosphere of an oxidizing gas such as air or oxygen, in anatmosphere of mixed gas consisting of any of the oxidizing gases and aninert gas such as nitrogen or argon at a predetermined temperature tilla desired melt viscosity can be obtained. The heat treatment temperatureis usually selected from 170 to 280° C., preferably from 200 to 270° C.The heat treatment time is usually selected from 0.5 to 100 hours,preferably 2 to 50 hours. If the heat treatment temperature and time areadequately controlled, the target viscosity level can be obtained. Theheat treatment apparatus can be an ordinary hot air dryer for use underreduced pressure or having high sealing capability, or a rotary heater,or a heater with stirring blades. However, for efficient and morehomogeneous treatment, it is preferred to use a rotary heater or aheater with stirring blades.

[0119] A particular method for heat-treating PPS in an atmosphere of aninert gas such as PPS or under reduced pressure is, for example, toheat-treat in an atmosphere of an inert gas such as nitrogen or underreduced pressure at a heat treatment temperature of 150 to 280° C.,preferably 200 to 270° C. for heat treatment time period of 0.5 to 10hours, preferably 2 to 50 hours. The heat treatment apparatus can be astationary heater, a rotary heater or a heater with stirring blades, butfor efficient and more homogeneous treatment, it is preferred to use arotary heater or a heater with stirring blades.

[0120] As particular methods for washing PPS using an organic solvent,the following methods can be exemplified. The organic solvent used forwashing is not especially limited if it does not act, for example, fordecomposing PPS. Such organic solvents include, for example,nitrogen-containing polar solvents such as N-methylpyrrolidone,dimethylformamide and dimethylacetamide, sulfoxide/sulfone solvents suchas dimethyl sulfoxide and dimethyl sulfone, ketone solvents such asacetone, methyl ethyl ketone, diethyl ketone and acetophenone, ethersolvents such as dimethyl ether, dipropyl ether and tetrahydrofuran,halogen-based solvents such as chloroform, methylene chloride,trichloroethylene, ethylene dichloride, dichloroethane,tetrachloroethane and chlorobenzene, alcohol/phenol solvents such asmethanol, ethanol, propanol, butanol, pentanol, ethylene glycol,propylene glycol, phenol, cresol and polyethylene glycol, aromatichydrocarbon solvents such as benzene, toluene and xylene. Among theseorganic solvents, it is preferred to use N-methylpyrrolidone, acetone,dimethylformamide, chloroform, etc. Any one of these organic solventscan be used, or two or more of them can also be used as a mixture. Amethod for washing using an organic solvent is, for example, to soak PPSinto an organic solvent, and as required, stirring or heating can alsobe employed. The washing temperature at which PPS is washed using anorganic solvent is not especially and any desired temperature of roomtemperature to about 300° C. can be selected. At a higher washingtemperature, the washing efficiency tends to be higher, but usually at awashing temperature of room temperature to 150° C., a sufficient effectcan be obtained.

[0121] It is preferred that the PPS washed with an organic solvent iswashed with cold or hot water several times to remove the remainingorganic solvent.

[0122] As particular methods for washing PPS using hot water, thefollowing methods can be exemplified. To exhibit a preferred effect ofchemically modifying PPS by washing with hot water, it is preferred thatthe water used is distilled water or deionized water. For operation ofhot water treatment, a predetermined amount of PPS is added into apredetermined amount of water, and they are heated and stirred atatmospheric pressure or in a pressure vessel. As for the ratio betweenPPS and water, it is preferred to use more water. Usually a bath ratioof 200 g or less of PPS per 1 liter of water is selected.

[0123] As particular methods for treating PPS using an acid, thefollowing methods can be exemplified. For example, a method of soakingPPS into an acid or an acid aqueous solution can be employed, and asrequired, stirring or heating can also be used. The acid used is notespecially limited, if it does not act for decomposing PPS. Such acidsinclude aliphatic saturated monocarboxylic acids such as formic acid,acetic acid, propionic acid and butyric acid, halo-substituted aliphaticsaturated carboxylic acids such as chloroacetic acid and dichloroaceticacid, aliphatic unsaturated monocarboxylic acids such as acrylic acidand crotonic acid, aromatic carboxylic acids such as benzoic acid andsalicylic acid, dicarboxylic acids such as oxalic acid, malonic acid,succinic acid, phthalic acid and fumaric acid, inorganic acidiccompounds such as sulfuric acid, phosphoric acid, hydrochloric acid,carbonic acid and silicic acid. Among them, acetic acid and hydrochloricacid can be more preferably used. It is preferred that the PPS treatedwith an acid is washed with cold or hot water several times for removingthe acid, salt and the like remaining on PPS. It is preferred that thewater used for washing is distilled water or deionized water, lest thepreferred effect of chemically modifying PPS by the acid treatmentshould be impaired.

[0124] It is most preferred that the polyester resin with polyethyleneterephthalate as the main component (hereinafter may be abbreviated asPET) used in this invention is polyethylene terephthalate homopolymer.However, the polyester resin can be any of those in which terephthalicacid used as an component is partially substituted by one or more ofisophthalic acid, 5-sodiumsulfoisophthalic acid,2,6-naphthalenedicarboxylic acid, diphenoxyethanedicarboxylic acid,adipic acid, sebacic acid, azelaic acid and dodecanedicarboxylic acid,or can be any of those in which ethylene glycol is partially substitutedby one or more of 1,4-butanediol, propylene glycol, neopentyl glycol,hexamethylene glycol, pentamethylene glycol, 1,4-cyclohexanedimethanol,glycerol, pentaerythritol, polyethylene glycol, polytetramethyleneglycol, etc. It is desirable that the copolymerization rate is kept in arange of 15 mol % or less, and it is more desirable that it is kept in arange of 5 mol % or less.

[0125] The molecular weight of the PET used in this invention is notespecially limited, but it is preferred to adequately select themolecular weight, since it relates to the conditions for inducing thespinodal decomposition described later. With regard to the intrinsicviscosity as a parameter relating to the molecular weight, a PET of 0.6or more (25° C., orthochlorophenol solution) can be used, and above all,a PET of 0.7 or more can be preferably used. It is preferred that theupper limit is 1.5 or less.

[0126] As the method for obtaining the polymer alloy of this invention,the method of using the spinodal decomposition described for the firstversion of this invention is preferred. Above all, the method of usingthe shear-induced spinodal decomposition can be preferably used, sincefiner structural control can be facilitated.

[0127] For inducing the spinodal decomposition, it is necessary to maketwo or more resins used as components miscible, and to subsequentlyarrive at the unstable state inside the spinodal curve. At first themethod for making the two or more resins used as components miscible canbe a solvent casting method or a melt blending method. A solvent castingmethod refers to a method in which after dissolving into a commonsolvent, the solution is transformed into a film or the like by means ofspray drying, freeze drying, solidification in a non-solvent substanceor solvent evaporation. A melt blending method refers to a method inwhich resins of a partially miscible system or of an immiscible systemare melt blended, to be made miscible. Among them, a melt blendingmethod that is a dry process free from the use of any solvent can bepractically preferably used. For inducing the spinodal decomposition ina polymer alloy containing PPS and PET, PPS and PET are made miscibleand subsequently brought to the unstable state inside the spinodalcurve.

[0128] At first the method for making the two or more resins used ascomponents miscible can be a solvent casting method or a melt blendingmethod. A solvent casting method refers to a method in which afterdissolving into a common solvent, the solution is transformed into afilm or the like by means of spray drying, freeze drying, solidificationin a non-solvent substance or solvent evaporation. A melt blendingmethod refers to a method in which resins of a partially miscible systemor of an immiscible system are melt blended, to be made miscible. Amongthem, a melt blending method that is a dry process free from the use ofany solvent can be practically preferably used.

[0129] In the case where a polymer alloy of a partially miscible systemis used, the resins of a partially miscible system are melt blended forbeing made miscible under the conditions to allow it, and cooled forinducing the spinodal decomposition. In the case where a polymer alloyof an immiscible system is used, it is possible to use the phaseseparation caused by the so-called shear induced spinodal decompositionas described for the first version of this invention, in which thepolymer alloy is melt blended under high shear flow, for being mademiscible, and decomposed in phase under no shear flow. The shear inducedphase dissolution and phase decomposition of an immiscible system can bemore preferably used, since the wavelength of concentration fluctuationin the early stage of spinodal decomposition can be easily shortenedcompared with that of a partially miscible system, as described for thefirst version of this invention.

[0130] In the case where PPS and PET are melt blended, if all the resinsused respectively have such a molecular weight as usually used formolding into fibers, three-dimensional molded article or the like, theyshow the shear induced phase dissolution and phase decomposition of animmiscible system, and if they are melt blended under high shear flow,they can be made miscible. On the other hand, since the differencebetween PPS and PET in solubility parameter is small, if either or bothof them are decreased in molecular weight, a partially miscible systemis formed, and they can be made miscible under lower shear flow.

[0131] In the case of a partially miscible system, for melt blending formaking miscible, an ordinary single-screw extruder or twin-screwextruder can be used, and among them, it is preferred to use atwin-screw extruder. The temperature for making miscible depends on thecombination between the molecular weight of PPS and that of PET, andcannot be generally specified. However, if preliminary experiments arecarried out based on the phase diagrams prepared for the cases where themolecular weights of PPS and/or PET are lowered as required for makingmiscible at the temperature of melt blending, the temperature can bedecided. It is preferred that the melt viscosity of the PPS with a lowmolecular weight is 0.01 to less than 5 Pa.s, and it is preferred thatthe intrinsic viscosity of the PET with a low molecular weight is lessthan 0.6. The lower limit depends on the composition ratio of PPS andPET and cannot be generally specified. A PET with any lower value can beused, if a desired molding method can be used for molding.

[0132] For inducing the spinodal decomposition in the polymer alloy mademiscible, the temperature and other conditions for arriving at theunstable state depend on the combination between the molecular weight ofPPS and that of PET, and cannot be generally specified. However, theycan be decided if simple preliminary experiments are carried out basedon aforesaid phase diagrams.

[0133] In the case of an immiscible system, a polymer alloy consistingof PPS and PET, the molecular weights of which are kept in the aforesaidusually used ranges, can be used. For making miscible by melt blendingunder shear flow, an ordinary single-screw extruder or twin-screwextruder can be used. Above all, it is preferred to use a twin-screwextruder with its screws arranged to allow application of high shearflow. The temperature for making miscible, the temperature for inducingthe spinodal decomposition and other conditions depend on thecombination between the molecular weight of PPS and that of PET, andcannot be generally specified. However, they can be decided by carryingout simple experiments based on the phase diagrams prepared undervarious shearing conditions.

[0134] The temperature and other conditions for inducing the spinodaldecomposition under no shear flow in the polymer alloy made miscibledepend on the combination between the molecular weight of PPS and thatof PET and cannot be generally specified. However, they can be decidedby carrying out simple experiments based on the phase diagrams preparedunder various shearing conditions. For more effectively making thestructure finer by the shear induced spinodal decomposition, it ispreferred to select the combination between the molecular weight of PPSand that of PET to ensure that the phase diagrams prepared undershearing conditions change more greatly.

[0135] After phase separation has been caused by the spinodaldecomposition, it is only required to fix the structure when a desiredwavelength of concentration fluctuation has been reached. The method forfixing the structural product achieved by the spinodal decomposition canbe a method of fixing the structure(s) of either or both of the phasesseparated by quick cooling or the like, or a method of fixing thestructure using the phenomenon that crystallization does not allow freemotion. Furthermore, in the process from the intermediate stage to thelate stage in which the wavelength increases, it can happen that onephase becomes discontinuous due to the influence of the compositionratio or interfacial tension, to change from the aforesaid co-continuousstructure to a dispersed structure. In this case, it is only required tofix the structure when the desired distance between particles has beenreached.

[0136] In the polymer alloy of this invention, it is necessary that thePPS resin and the PET resin in the resin composition are structurallycontrolled to ensure a co-continuous structure with the wavelength ofconcentration fluctuation kept in a range from 0.001 to 2 μm or adispersed structure with the distance between particles kept in a rangefrom 0.001 to 2 μm. For obtaining further excellent mechanicalproperties, it is preferred to control for ensuring a co-continuousstructure with the wavelength of concentration fluctuation kept in arange from 0.001 to 1.2 μm, or a dispersed structure with the distancebetween particles kept in a range from 0.001 to 1.2 μm, and it is morepreferred to control for ensuring a co-continuous structure with thewavelength of concentration fluctuation kept in a range from 0.001 to 1μm, or a dispersed structure with the distance between particles kept ina range from 0.001 to 1 μm. It is further more preferred to control forensuring a co-continuous structure with the wavelength of concentrationfluctuation kept in a range from 0.001 to 0.8 μm, or a dispersedstructure with the distance between particles kept in a range from 0.001to 0.8 μm.

[0137] Furthermore, to the polymer alloy of this invention, a thirdcomponents such as a copolymer, for example, a block copolymer, graftcopolymer or random copolymer respectively containing PPS and PET can bepreferably added, for such reasons that the free energy at the interfacebetween the separated phases can be lowered and that the wavelength ofconcentration fluctuation in the co-continuous structure or the distancebetween particles in the dispersed structure can be easily controlled.In this case, since the third components such as a copolymer is usuallydistributed into the respective phases of the polymer alloy consistingof two resins contained as components excluding the third component, thepolymer alloy obtained can be handled like the polymer alloy consistingof two resins contained as components.

[0138] The composition ratio of the polymer alloy of this invention isnot especially limited, but it is usually preferred that the amount ofPPS is 3 wt % or more per 100 wt % in total of PPS and PET. Morepreferred is 10 wt % or more, and further more preferred is 40 wt % ormore. As a preferred composition ratio for effectively exhibiting theproperties of PPS resin, it is preferred that the amount of PPS is in arange from 60 to 95 wt %, especially in a range from 65 to 95 wt % per100 wt % in total of PPS and PET.

[0139] In this invention, to further improve the strength, dimensionalstability, and so on, a filler can be used as required. The form of thefiller can be either fibrous or non-fibrous, and a fibrous filler and anon-fibrous filler can also be used in combination. Such fillers includefibrous fillers such as glass fibers, glass milled fibers, carbonfibers, potassium titanate whiskers, zinc oxide whiskers, aluminumborate whiskers, aramid fibers, alumina fibers, silicon carbide fibers,ceramic fibers, asbestos fibers, gypsum fibers and metal fibers, andnon-fibrous fillers, for example, silicates such as wollastonite,zeolite, sericite, kaolin, mica, clay, pyrophyllite, bentonite,asbestos, talc and alumina silicate, metal compounds such as alumina,silicon oxide, magnesium oxide, zirconium oxide, titanium oxide and ironoxide, carbonates such as calcium carbonate, magnesium carbonate anddolomite, hydroxides such as magnesium hydroxide, calcium hydroxide andaluminum hydroxide, glass beads, ceramic beads, boron nitride, siliconcarbide, etc. They can be hollow, and two or more of these fillers canalso be used together. It is preferred that these fibrous and/ornon-fibrous fillers are preliminarily treated with a coupling agent suchas an isocyanate-based compound, organic silane-based compound, organictitanate-based compound, organic borane-based compound or epoxycompound, since more excellent mechanical strength can be obtained.

[0140] In the case where such a filler is used, the amount is notespecially limited, but it is usually preferred to use 30 to 400 partsby weight of a filler per 100 parts by weight of the PPS resin.

[0141] To the polymer alloy of this invention, ordinary additives can beadded to such an extent that the effect of this invention is notimpaired. The additives include a plasticizer such as a polyalkyleneoxide oligomer-based compound, thioether-based compound, ester-basedcompound or organic phosphorus compound, crystal nucleating agent suchas talc, kaolin, organic phosphorus compound or polyether ether ketone,releasing agent such as a polyolefin-based compound, silicone-basedcompound, long chain aliphatic ester-based compound or long chainaliphatic amide-based compound, anticorrosive, coloration preventive,antioxidant, thermal stabilizer, lubricant such as lithium stearate oraluminum stearate, ultraviolet light preventive, colorant, flameretarder, foaming agent, etc.

[0142] These additives can be mixed at any desired stage while thepolymer alloy of this invention is manufactured. For example, suchmethods as a method of adding simultaneously when at least two resinsused as components are mixed, a method of adding after two resins usedas components have been melt blended, and a method of adding at first toeither of the resins, melt blending and mixing the remaining resin canbe used.

[0143] The polymer alloy of this invention can be molded by a desiredmethod into fibers, film, sheet or molded article, etc. The moldingmethod can be, for example, melt spinning, injection molding, extrusionmolding, inflation molding, or blow molding, etc. Above all, it ispreferred to melt-spin for use as fibers.

[0144] This invention is described below based on examples.

[0145] In the examples, the following raw materials were used.

[0146] PBT-1: Polybutylene terephthalate (“Toraycon (registeredtrademark)” 1100 S, glass transition temperature 32° C., crystal meltingtemperature 220° C., produced by Toray Industries, Inc.)

[0147] PBT-2: Polybutylene terephthalate (“Toraycon (registeredtrademark)” 1050S, glass transition temperature 32° C., crystal meltingtemperature 220° C., produced by Toray Industries, Inc.)

[0148] PBT-3: Polybutylene terephthalate resin (intrinsic viscosity 1.00(25° C., orthochlorophenol solution))

[0149] PC-1: Aromatic polycarbonate (“Iupilon (registered trademark)”S2000, glass transition temperature 151° C., produced by MitsubishiEngineering Plastic Co., Ltd.)

[0150] PC-2: Aromatic polycarbonate (“Iupilon (registered trademark)”H4000, glass transition temperature 151° C., produced by MitsubishiEngineering Plastic Co., Ltd.)

[0151] PC-3: Aromatic polycarbonate (“Toughlon” A1900, glass transitiontemperature 151° C., produced by Idemitsu Petrochemical Co., Ltd.)

[0152] AS-1: Styrene-acrylonitrile copolymer (“Toyolac (registeredtrademark)” 1050B, glass transition temperature 102° C., produced byToray Industries, Inc.)

[0153] PPS-1: PPS resin (PPS resin produced by polymerization asdescribed in the following reference example)

[0154] PET-1: Polyethylene terephthalate resin (intrinsic viscosity 0.62(25° C., orthochlorophenol solution))

[0155] Inert particles: Wet process silica with an average particle sizeof 2.5 μm (secondary diameter)

[0156] Releasing agent: Ethylene glycol montanic ester (Licowax(registered trademark) E, produced by Clariant (Japan) K.K.)

[0157] E-1: Ester interchange preventive (“Adekastab” AX-71 produced byAsahi Denka Kogyo K.K.)

[0158] X-1: Styrene-containing acrylic graft copolymer (“Paraloid”EXL2615, average particle size 0.1 to 0.6 μm, produced by KurehaChemical Industry Co., Ltd.)

REFERENCE EXAMPLE Polymerization for Obtaining PPS Resin (PPS-1)

[0159] An autoclave with a stirrer was charged with 6.004 kg (25 moles)of sodium sulfide nonahydrate and 4.5 kg of N-methyl-2-pyrrolidone(NMP), and while nitrogen was introduced, the temperature was graduallyraised to 205° C., to distil away 3.6 liters of water. Then, thereaction vessel was cooled to 180° C., and 3.719 kg (25.3 moles)of,1,4-dichlorobenzene and 3 kg of NMP were added. The reaction vesselwas sealed under nitrogen and heated to 270° C., to carry out a reactionat 274° C. for 1.5 hours. After cooling, the reaction product was washedwith warm water twice, to obtain a slurry. The slurry was placed in anautoclave with a stirrer together with 3 kg of ion exchange water, andthe mixture was heated to 190° C., and cooled to room temperature. Thereaction mixture was filtered, and the residue was washed with hot waterseveral times. It was filtered, and the residue was dried at 80° C. for24 hours under reduced pressure to obtain 2.48 kg of PPS resin. The PPSresin was of straight chain and had a melt viscosity of 80 Pa.s (320°C., shear rate 1000 sec⁻¹), a glass transition temperature of 89° C. anda crystal melting temperature of 280° C.

[0160] The melt viscosity was measured using a capillary type meltviscosity measuring instrument (CAPIROGRAPH-IC produced by Toyo SeikiSeisakusho, Ltd.) with orifice L/D=20 (inner diameter 1 mm), and theglass transition temperature and the crystal melting temperature weremeasured at a heating rate of 20° C./min using DSC (DSC-7 produced byPerkin-Elmer).

[0161] In the examples, the following evaluation methods were used.

[0162] (1) Evaluation of Phase Structure

[0163] A. Observation Using an Electron Microscope

[0164] A very thin section was cut out of a sample using anultra-microtome. In this case, in the case where the sample contained apolycarbonate, the polycarbonate was dyed using an iodine dyeing method,before cutting out a very thin section. The section was magnified100,000 magnifications under Model H-7100 Transmission ElectronMicroscope produced by Hitachi, Ltd., to observe the phase structure.

[0165] B. Observation Using Small-Angle X-Ray Scattering

[0166] The wavelength of concentration fluctuation of a co-continuousstructure was measured using small-angle X-ray scattering. The X-raygenerator was RU-200 produced by Rigaku Corporation, and CuKα radiationwas used as a radiation source. A scattering photograph was taken at anoutput of 50 kV/150 mA, a slit diameter of 0.5 mm and a camera radius of405 mm for an exposure time of 120 minutes using Kodak DEF-5 film. Fromthe peak position (θm) in small-angle X-ray scattering, the wavelengthof concentration fluctuation (Λm) was calculated from the followingformula.

Λm=(λ/2)/sin(θm/2)

[0167] The distance between particles of a dispersed structure was alsoobtained similarly.

[0168] (2) Measurement of Glass Transition Point

[0169] Model RDC-220 DSC produced by Seiko Instruments Inc. was used formeasuring at a heating rate of 20° C./min in a nitrogen atmosphere.

WORKING EXAMPLES 1 to 5

[0170] Raw materials with a composition ratio shown in Table 1 were fedinto a parallel plates type shear flow-applying device (CSS-430 producedby Linekam), and molten at a kneading temperature of 250° C. Then, ashear field was applied at the shear rate shown in Table 1. Every samplewas observed in the portion subjected to the shear field at the shearrate shown in Table 1, and it was confirmed that none of the samples hadany structure. Each of the samples was immediately quickly cooled in icywater to fix its structure, and the phase structure of the obtainedsample was observed with a transmission electron microscope. It wasconfirmed that none of the samples had structure of 0.001 μm or more,and that they were made miscible. So, it was found that this series wasmade miscible at 250° C. under the shearing condition shown in Table 1.

[0171] Next, raw materials with a composition ratio shown in Table 1.were fed into a twin-screw extruder (PCM-30 produced by Ikegai Kogyo)set at an extrusion temperature of 250° C., and the gut discharged fromthe die was immediately quickly cooled in icy water, to obtain a gutwith its structure fixed. All the guts were transparent. The phasestructures of the guts were observed with a transmission electronmicroscope, and it was confirmed that none of the samples had structureof 0.001 μm, and that they were made miscible. So, it was found thatthis series was made miscible under the shear flow in an extruder set atan extrusion temperature of 250° C. The glass transition temperatures of100 mg samples cut out of the guts were measured using DSC, and theresults are shown in Table 1.

[0172] This series was of a system with an LCST type phase diagram, andhad the miscible region expanded under the shear flow of an extruder.

[0173] Furthermore, a 100 μm thick section was cut out of each of theguts, and heat-treated at the temperature shown in Table 1, and duringthe heat treatment, the structure-forming process was traced usingsmall-angle X-ray scattering. In every sample, one minute after start ofheat treatment, a peak appeared. Furthermore, when the peak wasobserved, a tendency of strength increase was observed without anychange in the peak position. The stage in which the strength increaseswithout any change in the peak position in small-angle X-ray scatteringcorresponds to the initial stage of spinodal decomposition. Table 1shows the wavelengths of concentration fluctuation (Λm) calculated fromthe peak positions (θm).

[0174] The sections subject to the above-mentioned heat treatmentprocess were partially quickly cooled in icy water to fix theirstructures, and the phase structures were observed with a transmissionelectron microscope. Every sample was observed to have a co-continuousstructure.

[0175]FIG. 1 is a transmission electron microscope photograph showingthe structure obtained in the early stage of spinodal decomposition ofWorking Example 2. In the photograph, the black portions indicate thephase with the polycarbonate as a main component, and white portionsindicate the phase with polybutylene terephthalate as a main component.

[0176] The sections measured using the small-angle X-ray scattering hadstructures formed in the early stage, and subsequently continuouslyheat-treated at the respective temperatures for 10 minutes in total, forforming structures. With the samples, the wavelengths of concentrationfluctuation were observed with small-angle X-ray scattering as describedabove, and their phase structures were observed on transmission electronmicroscope photographs. The results are shown in Table 1.

[0177]FIG. 2 shows the transmission electron microscope photograph ofthe structure obtained after continuing heat treatment for 10 minutes inWorking Example 2. In the photograph, black portions indicate the phasewith the polycarbonate as a main component, and white portions show thephase with polybutylene terephthalate as a main component.

[0178] The guts with their structures fixed by quick cooling werehot-pressed into sheets (0.2 mm thick). The hot pressing conditions areshown in Table 1. From the obtained sheets, 100 μm thick sections werecut out, and as described above, the wavelengths of concentrationfluctuation or the distances between particles were obtained usingsmall-angle X-ray scattering, and phase structures were observed ontransmission electron microscope photographs. The results are shown inTable 1. Also from the results, it can be seen that the heat treatmentby means of a hot press also allowed the same structures to be formed asthose in the samples cut out of the guts. From the sheets, 50 mm long,10 mm wide and 0.2 mm thick samples were cut out, and their tensilestrengths and tensile elongations were measured at an inter-chuckdistance of 20 mm and a tensile speed of 10 mm/min. Furthermore,specimens were taken from the sheets using a die cutting press, andtensile impact strengths were measured according to ASTM D 1822. Theresults of measurement are shown in Table 1.

[0179] Furthermore, each of the guts with their structures fixed byquick cooling was pelletized into pellets using a strand cutter. Theobtained pellets were used to obtain a sheet by an extrusion method. Thepellets were fed into a single-screw extruder (40 mm diameter) set at anextrusion temperature of 250° C. and having a T die at the tip, with theretention time set at 10 minutes, to produce a sheet. For producing thesheet, a casting drum made of hard chromium and having a mirror finishedsurface with the temperature kept at 50° C. was placed below the T die.The resin composition discharged from the mouthpiece of the T die wascast onto the casting drum, and passed over a second drum kept at 50°C., and further between rolls set at 5 m/min for keeping the take-upspeed constant, being taken up by a take-up roll, to obtain a sheet. Thethickness of the obtained sheet was 0.1 mm. Furthermore, it wastransparent. The phase structure of the sheet was observed using atransmission electron microscope. It was confirmed that every sample hada co-continuous structure. Furthermore, from the obtained sheet, a 10 mgsample was cut out, and its glass transition temperature and heatingcrystallization temperature were measured using DSC. The results areshown in Table 1. From the results of measurement with DSC, it was foundthat each sheet obtained had two glass transition temperatures. Thissuggests that phase separation occurred during the melting time in theextruder. To confirm it, further samples were cut out from the obtainedsheets and the structure-forming processes during heat treatment at 250°C. were traced using small-angle X-ray scattering. With every sample, apeak existed, and when the peak was observed, a tendency of strengthincrease was observed for 1 minute thereafter without any change in thepeak position. The stage in which the strength increased without anychange in the peak position in the small-angle X-ray scatteringcorresponds to the coarsening in the early stage of spinodaldecomposition. Table 1 shows the wavelengths of concentrationfluctuation in the early stage calculated as described above. From theabove results, it can be considered that the spinodal decompositionoccurred again during the melting time in the extruder, and that, as aresult, a co-continuous structure could be observed in each of theobtained sheets.

[0180] From each of the obtained sheets, a 100 mm square sample was cutout, fastened using clips on its four sides, preheated at 90° C. for 60seconds, and stretched simultaneously biaxially at a stretching speed of2000%/min at a stretching ratio of 3 times in an oven kept at 90° C.With each of the stretched samples, as described before, the wavelengthof concentration fluctuation was observed using small-angle X-rayscattering, and the phase structure was observed on a transmissionelectron microscope photograph. The results are shown in Table 1. Ineach of the stretched samples, the wavelength of concentrationfluctuation increased compared with that before stretching, and it canbe considered that the heat treatment during stretching causedcoarsening. Furthermore, from each of the stretched sheets, a 50 mmlong, 10 mm wide and 0.03 mm thick sample was cut out, and its tensilestrength and tensile elongation were measured at an inter-chuck distanceof 20 mm at a tensile speed of 10 mm/min, and the results are shown inTable 1.

COMPARATIVE EXAMPLE 1

[0181] Raw materials were melt blended, discharged from a die, andimmediately quickly cooled in icy water, to obtain a gut with itsstructure fixed as described for Working Example 2, except that theextrusion temperature was set at 280° C. The gut was cloudy. When, thegut was magnified 1000 magnifications under a transmission electronmicroscope for observation, heterogeneously dispersed structure of 0.5μm and more were observed. So, it can be seen that the system was notmade miscible under the shear flow in the extruder with an extrusiontemperature of 280° C. Also for this sample, the mechanical propertieswere measured and the phase structure was observed as described forWorking Example 2, and the results are shown in Table 1.

COMPARATIVE EXAMPLE 2

[0182] A sample was obtained as described for Working Example 2, exceptthat the heat treatment was carried out at a temperature of 220° C. for10 minutes. The mechanical properties of the sample were measured, andits phase structure was observed. The results are shown in Table 1.However, the wavelength of concentration fluctuation of this sample wasmeasured using a small-angle light scattering device. In the case wherethe wavelength of concentration fluctuation in the early stage does notbecome sufficiently small because of low heat treatment temperature asin this example, if coarsening is carried out to obtain a sufficientdifference between the concentrations of both the components, it becomesdifficult to control the wavelength of concentration fluctuation withinthe scope of this invention. Furthermore, as in this example, if thewavelength of concentration fluctuation does not conform to thisinvention, a sample with poor mechanical properties only can beobtained.

COMPARATIVE EXAMPLE 3

[0183] A sample was obtained as described for Working Example 4, exceptthat quick cooling and heat treatment were not carried out after thestructure was formed in the early stage of spinodal decomposition. Themechanical properties of the sample were measured, and the phasestructure was observed. The results are shown in Table 1.

[0184] As can be seen from the results of Working Examples 1 to 5 andComparative Examples 1 to 3, the polymer alloys with a specificstructure of this invention have excellent strength and toughness. TABLE1 Working Working Working Working Example 1 Example 2 Example 3 Example4 Composition PC-1 (wt %) 70 50 30 50 PBT-1 (wt %) 30 50 70 50 KneadingShearing rate (sec⁻¹) 1000 1000 1000 1000 condition Miscibility MiscibleMiscible Miscible Miscible Extruded gut Miscibility Miscible MiscibleMiscible Miscible Glass transition (° C.) 85 (single) 78 (single) 69(single) 77 (single) temperature Extruded and Heat treatment 250° C. × 1min 250° C. × 1 min 250° C. × 1 min 270° C. × 1 min heat-treatedconditions gut Initial structure Co-continuous Co-continuousCo-continuous Co-continuous structure structure structure structureWavelength of (μm) 0.01 0.01 0.01 0.005 concentration fluctuation Heattreatment 250° C. × 10 min 250° C. × 10 min 250° C. × 10 min 270° C. ×10 min conditions Polymer alloy Dispersed Co-continuous DispersedCo-continuous structure structure structure structure structureWavelength of (μm) 0.13 0.11 0.12 0.04 concentration fluctuation ordistance between particles Pressed and Heat treatment 250° C. × 10 min250° C. × 10 min 250° C. × 10 min 270° C. × 10 min heat-treatedconditions sheet Polymer alloy Dispersed Co-continuous DispersedCo-continuous structure structure structure structure structureWavelength of (μm) 0.14 0.12 0.12 0.05 concentration fluctuation ordistance between particles Tensile strength (MPa) 71 66 62 73 Tensileelongation (%) 320 270 240 310 Tensile impact (J/cm²) 122 113 103 127strength Extruded sheet Initial structure Co-continuous Co-continuousCo-continuous — structure structure structure Wavelength of (μm) 0.0080.008 0.008 — concentration fluctuation Glass transition (° C.) 69, 10161, 96 53, 85 — temperature Heating crystallization (° C.) 122 112 105 —temperature Stretched Polymer alloy Co-continuous Co-continuousCo-continuous — sheet structure structure structure structure Wavelengthof (μm) 0.07 0.08 0.08 — concentration fluctuation or distance betweenparticles Tensile strength (MPa) 95 90 86 — Tensile elongation (%) 290350 410 — Working Comparative Comparative Comparative Example 5 Example1 Example 2 Example 3 Composition PC-1 (wt %) 50 50 50 50 PBT-1 (wt %)50 50 50 50 Kneading Shearing rate (sec⁻¹) 1000 — — — conditionMiscibility Miscible — — — Extruded gut Miscibility Miscible ImmiscibleMiscible Miscible Glass transition (° C.) 77 (single) 32, 151 77(single) 77 (single) temperature Extruded and Heat treatment 230° C. × 1min 250° C. × 1 min 220° C. × 1 min 270° C. × 1 min heat-treatedconditions gut Initial structure Co-continuous Dispersed Co-continuousCo-continuous structure structure structure structure Wavelength of (μm)0.07 — 0.5 0.005 concentration fluctuation Heat treatment 230° C. × 10min 250° C. × 10 min 220° C. × 10 min — conditions Polymer alloyCo-continuous Dispersed Co-continuous structure structure structurestructure Wavelength of (μm) 0.81 — 2.1 concentration fluctuation ordistance between particles Pressed and Heat treatment 230° C. × 10 min250° C. × 10 min 220° C. × 10 min 270° C. × 1 min heat-treatedconditions sheet Polymer alloy Co-continuous Dispersed Co-continuousCo-continuous structure structure structure structure structureWavelength of (μm) 0.8 — 2.1 0.005 concentration fluctuation or distancebetween particles Tensile strength (MPa) 59 41 49 43 Tensile elongation(%) 210 45 77 60 Tensile impact (J/cm²) 95 15 38 45 strength Extrudedsheet Initial structure — Dispersed — — structure Wavelngth of (μm) — —— — concentration fluctuation Glass transition (° C.) — 32, 151 — —temperature Heating crystallization (° C.) — Not detected — —temperature Stretched Polymer alloy — Dispersed — — sheet structurestructure Wavelength of (μm) — — — — concentration fluctuation ordistance between particles Tensile strength (MPa) — 75 — — Tensileelongation (%) — 130 — —

WORKING EXAMPLES 6 and 7

[0185] Raw materials with a composition ratio shown in Table 2 were fedinto a parallel plates type shear flow-applying device (CSS-430 producedby Linekam), and molten at a kneading temperature of 240° C. Then, ashear field was applied at the shear rate shown in Table 2. Every samplewas observed in the portion subjected to the shear field at the shearrate shown in Table 2, and it was confirmed that none of the samples hadany structure. Each sample was immediately quickly cooled in icy water,to obtain a sample with its structure fixed. The phase structure of theobtained sample was observed with a transmission electron microscope. Itwas confirmed that none of the samples had structure of 0.001 μm ormore, and that they were made miscible. So, it was found that thisseries was of a system that could be made miscible at 240° C. under theshearing condition shown in Table 2.

[0186] Raw materials with a composition ratio shown in Table 2 were fedinto a twin-screw extruder (PCM-30 produced by Ikegai Kogyo) set at anextrusion temperature of 240° C., and the gut discharged from the diewas immediately quickly cooled in icy water, to fix its structure. Everygut was transparent. The phase structure of the gut was observed with atransmission electron microscope, and it was confirmed that none of thesamples had structure of 0.001 μm or more, and that they were mademiscible. So, it can be seen that this series could be made miscibleunder the shear flow in an extruder set at an extrusion temperature of240° C.

[0187] This series was of a system with an LCST type phase diagram, andhad the miscible region expanded under the shear flow of an extruder.

[0188] Furthermore, a 100 μm thick section was cut out of each of theguts and heat-treated at the conditions shown in Table 2, and during theheat treatment, the structure-forming process was traced usingsmall-angle X-ray scattering. In every sample, one minute after start ofheat treatment, a peak appeared. Furthermore, when the peak wasobserved, a tendency of strength increase was observed without anychange in the peak position. The stage in which the strength increaseswithout any change in the peak position in small-angle X-ray scatteringcorresponds to the initial stage of spinodal decomposition. The phasestructures were observed as described for Working Example 1, and theresults are shown in Table 2.

[0189] The sections measured using small-angle X-ray scattering werecontinuously heat-treated for 10 minutes in total as described forWorking Example 1, except that the temperature was changed as shown inTable 2, and the phase structures were observed. The results are shownin Table 2.

[0190] Furthermore, pressed sheets were produced as described forWorking Example 1, except that the temperature was changed as shown inTable 2, and the phase structures were observed. The results are shownin Table 1. From the results, it can be seen that even if a hot press isused for heat treatment, a structure could be formed as in the samplescut out of the guts.

[0191] Subsequently, from the sheets, 85 mm long, 20 mm wide and 0.8 mmthick strip samples were cut out. Each specimen was held at one endportion of 20 mm and fastened to be horizontal like a cantilever. Thespecimens were placed in an oven of 100, 110, 120, 130, 140, 150 or 160°C. for 60 minutes, and for each specimen, the vertical distance of thetip opposite to the held portion, hanging down by its own weight wasmeasured. The relation between the hanging-down vertical distance ateach temperature and the temperature was plotted, and the temperatureintersecting with a hanging-down vertical distance of 3 mm wasidentified as the heat resistance temperature. The value is shown inTable 2.

COMPARATIVE EXAMPLE 4

[0192] Raw materials were melt blended, discharged from a die, andimmediately quickly cooled in icy water, to obtain a gut with itsstructure fixed as described for Working Example 6, except that theextrusion temperature was set at 290° C. The gut was cloudy. The phasestructure of the gut was observed under a transmission electronmicroscope, and heterogeneously dispersed structure of 0.5 μm and morewere observed. So, it can be seen that this sample was of a system notmade miscible under the shear flow in an extruder with an extrusiontemperature of 290° C. Also for this sample, the heat resistance wasmeasured as described for Working Example 6, and the phase structure wasobserved. The results are shown in Table 2.

[0193] From the results of Working Examples 6 and 7 and ComparativeExample 4, the polymer alloys with a specific structure have excellentheat resistance. TABLE 2 Working Working Comparative Example 6 Example 7Example 4 PC-1 (wt %) 50 50 50 AS-1 (wt %) 50 50 50 Kneading conditionShearing rate (sec⁻¹⁾ 1000 1000 — Miscibility Miscible Miscible —Extruded gut Miscibility Miscible Miscible Immiscible Extruded and heat-Heat treatment 240° C. × 1 min 270° C. × 1 min 240° C. × 1 min treatedgut conditions Initial structure Co-continuous Co-continuous Dispersedstructure structure structure Wavelength of (μm) 0.01 0.08 —concentration fluctuation Heat treatment 240° C. × 10 min 270° C. × 10min 240° C. × 10 min conditions Polymer alloy Co-continuous DispersedDispersed structure structure structure structure Wavelength of (μm)0.12 0.78 — concentration fluctuation or distance between particlesHeat-treated sheet Heat treatment 240° C. × 10 min 270° C. × 10 min 240°C. × 10 min conditions Polymer alloy Co-continuous Dispersed Dispersedstructure structure structure structure Wavelength of (μm) 0.13 0.79 —concentration fluctuation or distance between particles Heat resistance(° C.) 141 133 115 temperature

[0194] As described above, the polymer alloy of this invention has suchproperties as excellent strength and toughness or excellent heatresistance depending on the resins used in combination, and can beusefully used as a structural material having such properties Thepolymer alloy of this invention also has an excellent property ofregularity, and can also be usefully used as a functional material basedon the regularity.

[0195] In the following Working Examples 8 to 18 and ComparativeExamples 5 to 10, the following evaluation methods were used.

[0196] (1) Manufacture of Specimens for Evaluation

[0197] Obtained pellets were injection-molded using an injection moldingmachine (PS-60E9DSE) produced by Nissei Plastic Industrial Co., Ltd. setat 240° C., 250° C., 260° C. and 260° C. from the hopper bottom towardthe tip, at a mold temperature of 80° C. in molding cycles consisting of10 seconds of follow-up pressure application and 30 seconds of cooling,to produce ⅛″ thick ASTM No. 1 dumbbell specimens.

[0198] (2) Tensile Test

[0199] A ⅛″ thick ASTM No. 1 dumbbell specimen was measured usingUTA-2.5T Tensile Tester produced by Orientech according to ASTM D 638 ata gauge length of 114 mm at a strain rate of 10 mm/min. Working Examples8 to 12

[0200] Raw materials with a composition ratio shown in Table 3 were fedinto a twin-screw extruder set at an extrusion temperature of 260° C.,with its screws arranged to have two kneading zones and with the screwrotated speed set at 300 rpm. The gut discharged from the die was passedthrough a cooling bath filled with water kept at 10° C., taking 15seconds, for being quickly cooled to fix the structure. The gut waspelletized into pellets using a strand cutter. The retention time in thedie was 5 seconds. All the pellets of the respective working exampleswere transparent. The phase structures of the pellets were observedusing a transmission electron microscope, and it was confirmed that noneof the samples had structure of 0.001 μm or more, and that they weremade miscible.

[0201] The obtained pellets were molded into ⅛″ ASTM No. 1 dumbbellspecimens according to the above-mentioned manufacturing method. ForWorking Example 12, as shown in Table 3, a part of the releasing agentwas externally added to the pellets for subsequent molding. The ASTM No.1 dumbbells were used to carry out tensile tests according to ASTM D638. The results are shown in Table 3. Furthermore, cooling time onlywas shortened during molding, and the molded articles were taken out fortesting. The shortest cooling time after which the molded article couldbe taken out without deformation was obtained, and the result is shownin Table 3. If the shortest cooling time is shorter, productivity ishigher since the molding cycle time can be shortened.

[0202] From the molded articles produced under the aforesaid injectionmolding conditions, 100 μm thick sections were cut out, and their phasestructures were observed on transmission electron microscope photographsas described for the pellets. In the electron microscope photographs,co-continuous structures in which a polycarbonate phase dyed black and awhite polybutylene terephthalate phase formed continuous phasesrespectively were observed.

[0203] The wavelengths of concentration fluctuation in the co-continuousstructures were measured using small-angle X-ray scattering.

WORKING EXAMPLES 13 to 15

[0204] Melt blending was carried out to obtain pellets as described forWorking Examples 8 to 10, except that a die with a large inner volumewas used. The retention time in the die was 20 seconds. In theobservation made using a transmission electron microscope as describedfor Working Examples 8 to 10, fine co-continuous structures wereobserved. The wavelengths of concentration fluctuation obtained usingsmall-angle X-ray scattering are shown in Table 3. The molded articleswere evaluated as described for Working Examples 8 to 10, and theresults are shown in Table 3. TABLE 3 Working Working Working WorkingExample 8 Example 9 Example 10 Example 11 Composition PBT-2 parts by 7555 25 55 weight PC-2 parts by 25 45 75 45 weight Releasing agent partsby — — — 0.2 (internally added) weight Releasing agent parts by — — — —(externally added) weight Kneading Temperature ° C. 260 260 260 260conditions Screw speed rpm 300 300 300 300 Dwell time in die sec 5 5 5 5Cooling bath ° C. 10 10 10 10 temperature Pellets Structure MiscibleMiscible Miscible Miscible Wavelength of μm — — — — concentrationfluctuation Molded Molding method Injection Injection InjectionInjection article molding molding molding molding Structure Co- Co- Co-Co- continuous continuous continuous continuous Wavelength of μm 0.010.01 0.01 0.01 concentration fluctuation Tensile strength MPa 73 81 7782 Tensile elongation % More than More than More than More than 200 200200 200 Shortest cooling time sec 13 15 20 10 Working Working WorkingWorking Example 12 Example 13 Example 14 Example 15 Composition PBT-2parts by 55 75 55 25 weight PC-2 parts by 45 25 45 75 weight Releasingagent parts by 0.2 — — — (internally added) weight Releasing agent partsby 0.2 — — — (externally added) weight Kneading Temperature ° C. 260 260260 260 conditions Screw speed rpm 300 300 300 300 Dwell time in die sec5 20 20 20 Cooling bath ° C. 10 10 10 10 temperature Pellets StructureMiscible Co- Co- Co- continuous continuous continuous Wavelength of μm —0.008 0.005 0.008 concentration fluctuation Molded Molding methodInjection Injection Injection Injection article molding molding moldingmolding Structure Co- Co- Co- Co- continuous continuous continuouscontinuous Wavelength of μm 0.01 0.12 0.08 0.11 concentrationfluctuation Tensile strength MPa 82 65 76 72 Tensile elongation % Morethan More than More than More than 200 200 200 200 Shortest cooling timesec 5 13 16 20

COMPARATIVE EXAMPLES 5 and 6

[0205] Melt blending was carried out to obtain pellets as described forWorking Examples 8 to 11, except that the die used had a further largerinternal volume, that the screw rotated speed was 100 rpm, and that thetemperature of the cooling bath was 40° C. The retention time in the diewas 120 seconds. The obtained pellets were opaque, and in theobservation made using a microscope as described for Working Examples 8to 11, a dispersed structure or a co-continuous structure was observed.Since the wavelengths of concentration fluctuation were longer thanthose of Working Examples 8 to 11, they were obtained on electronmicroscope photographs. In the case where a dispersed structure wasshown, the distance between particles is shown instead of the wavelengthof concentration fluctuation. Furthermore, as described for WorkingExamples 8 to 11, the molded articles were evaluated, and the resultsare shown in Table 4. TABLE 4 Comparative Comparative Example 5 Example6 Composition PBT-2 parts by 75 25 weight PC-2 parts by 25 75 weightReleasing agent parts by — — weight Kneading Temperature ° C. 260 260conditions Screw speed rpm 100 100 Dwell time in die sec 120 120 Coolingbath ° C. 40 40 temperature Pellets Structure Dispersed DispersedWavelength of μm 1.1 0.9 concentration fluctuation or distance betweenparticles Molded Molding method Injection molding Injection moldingarticle Structure Dispersed Dispersed Wavelength of μm 1.5 1.1concentration fluctuation or distance between particles Tensile strengthMPa 45 48 Tensile elongation % 20 30 Shortest molding cycle sec 20 30

WORKING EXAMPLES 16 to 18

[0206] Raw materials with a composition ratio as shown in Table 5 weremelt blended to obtain pellets as described for Working Examples 8 to10. The obtained pellets were fed into a single-screw extruder (40 mmdiameter) set at an extrusion temperature of 250° C. and having a T dieat the tip, with the retention time set at 10 minutes, to produce afilm. For producing the film, a casting drum made of hard chromium andhaving a mirror finished surface with the temperature kept at 50° C. wasplaced below the T die. The resin composition discharged from themouthpiece of the T die was cast onto the casting drum, and passed overa second drum kept at 50° C., and further between rolls set at 5 m/minfor keeping the take-up speed constant, being taken up by a take-uproll, to obtain a film. The thickness of the obtained film was 0.1 mm.Furthermore, it was transparent. The phase structure of the film wasobserved using a transmission electron microscope, and it was confirmedthat every sample had a co-continuous structure. Furthermore, thewavelength of concentration fluctuation was measured using small-angleX-ray scattering. During film production, when the film was taken upusing the take-up roll, the film was sometimes wrinkled. The take-upwrinkling frequency was recorded. The wrinkling frequency per hour isshown in Table 5. If the wrinkling frequency is smaller, the pelletsallow more stable molding into a film and can be considered to be moreexcellent in productivity.

[0207] From each of the obtained films, a 100 mm square sample was cutout, fastened using clips on its four sides, preheated at 90° C. for 60seconds, and stretched simultaneously biaxially at a stretching speed of2000%/min at a stretching ratio of 3 times in an oven kept at 90° C.Also for each of the stretched samples, as described before, thewavelength of concentration fluctuation was observed using small-angleX-ray scattering, and the phase structure was observed on a transmissionelectron microscope photograph. The results are shown in Table 5. Ineach of the stretched samples, the wavelength of concentrationfluctuation increased compared with that before stretching, and it canbe considered that the heat treatment during stretching causedcoarsening. Furthermore, from each of the stretched sheets, a 50 mmlong, 10 mm wide and 0.03 mm thick sample was cut out, and its tensilestrength and tensile elongation were measured at an inter-chuck distanceof 20 mm at a tensile speed of 10 mm/min, and the results are shown inTable 5. TABLE 5 Working Working Working Comparative Comparative Example16 Example 17 Example 18 Example 7 Example 8 Composition PBT-2 parts by45 45 45 45 45 weight PC-2 parts by 55 55 55 55 55 weight Inactiveparticles parts by — 1 2 — 2 weight Kneading Temperature ° C. 260 260260 260 260 conditions Screw speed rpm 300 300 300 100 100 Dwell time indie sec 5 5 5 120 120 Cooling bath ° C. 10 10 10 40 40 temperaturePellets Structure Miscible Miscible Miscible Co- Co- continuouscontinuous Wavelength of μm — — — 0.5 0.5 concentration fluctuation FilmStructure Co- Co- Co- Dispersed Dispersed continuous continuouscontinuous Wavelength of 0.003 0.003 0.003 1.5 1.5 concentrationfluctuation or distance between particles Take-up wrinkling times/h 10 1Less than 30 20 frequency 0.5 Stretched Structure Co- Co- Co- StretchingStretching film continuous continuous continuous not allowed not allowedWavelength of μm 0.02 0.02 0.02 concentration fluctuation Tensilestrength MPa 100 100 100 Tensile elongation % 200 200 180

COMPARATIVE EXAMPLES 7 and 8

[0208] Raw materials shown in Table 5 were melt blended under the samekneading conditions as described for Comparative Example 5, to obtainpellets. The obtained pellets were opaque, and as a result ofobservation with an electron microscope, it was found that they had aco-continuous structure with a wavelength of concentration fluctuationof 0.5 μm. The pellets were molded into films by the same method asdescribed for Working Examples 16 to 18. The obtained films were opaque,and as a result of observation with an electron microscope, they werefound to have a dispersed structure with a distance between particles of1.5 μm. It was attempted to simultaneously biaxially stretch theobtained films by the same method as described for Working Examples 16to 18, but the films were broken and did not allow stretching.

[0209] From the results of Working Examples 8 to 18 and ComparativeExamples 5 to 8, it can be seen that if the polymer alloy pellets ofthis invention are used, they can be transformed into injection-moldedarticles and films with excellent mechanical properties at highproductivity. The polymer alloy pellets of this invention can usefullyused as a structural material based on these properties.

WORKING EXAMPLES 19 to 23

[0210] Raw materials with a composition ratio as shown in Table 6 werefed into a twin-screw extruder (PCM-30 produced by Ikegai Kogyo) set atan extrusion temperature of 250° C., having two kneading zones andrevolved at a high screw rotated speed of 300 rpm. The gut dischargedfrom the die was immediately quickly cooled in icy water to fix itsstructure. All the guts were transparent. The phase structures of theguts were observed with a transmission electron microscope, and it wasconfirmed that none of the samples had structure of 0.001 μm or more,and that they were made miscible. From the result, it can be seen thatthis series could be made miscible under the shear flow of an extruderset at an extrusion temperature of 250° C.

[0211] This series was of a system with an LCST type phase diagram, andhad the miscible region expanded under the shear flow of an extruder.

[0212] Furthermore, each of the guts made miscible was pelletized intopellets using a strand cutter. The pellets were fed into a single-screwextruder (30 mm diameter) set at an extrusion temperature of 250° C. andhaving a T die at the tip, to produce a film. For producing the film, acasting drum made of hard chromium and having a mirror finished surfacewith the temperature kept at 20° C. was placed right under (3 cm) the Tdie. The resin composition discharged from the mouthpiece of the T diewas cast onto the casting drum, and static electricity of 8 kV wasapplied to bring the film into contact with the casting drum, forquickly cooling it, to fix the structure. Furthermore, the film waspassed between rolls set at 5 m/min to keep the take-up speed constant,and taken up using a take-up roll, to obtain a film. The thickness ofthe obtained film was 0.1 mm. The obtained film was transparent. Thephase structure of the film was observed with a transmission electronmicroscope. It was confirmed that every sample had a co-continuousstructure or a dispersed structure. From the obtained films, furthersamples were cut out for measurement using small-angle X-ray scattering.With every sample, a peak was observed. Table 6 shows the wavelengths ofconcentration fluctuation (Λm) calculated from the peak positions (θm).

[0213] From the above results, it can be considered that when a film isformed, a miscible state is kept even under the shear flow in asingle-screw extruder, that after discharge from a T die, the spinodaldecomposition under no shear flow causes phase separation, and that thesubsequent quick cooling causes the structure to be fixed.

[0214] From the films, 50 mm long, 10 mm wide and 0.1 mm thick sampleswere cut out, and at an inter-chuck distance of 20 mm and a tensilespeed of 10 mm/min, the tensile strengths and tensile elongations weremeasured. The results are shown in Table 6.

[0215] From each of the obtained films, a 100 mm square sample was cutout, fastened using clips on its four sides, preheated at 90° C. for 60seconds, and simultaneously biaxially stretched at a stretching speed of2000%/min at a stretching ratio of 2 times or 4 times in an oven kept at90° C. Each of the stretched films was fastened on its four sides in analuminum frame and passed through an oven kept at 180° C. taking 15seconds, for heat treatment, to stabilize the phase structure of thestretched film. Also for each of the stretched samples, as describedbefore, the wavelength of concentration fluctuation was measured usingsmall-angle X-ray scattering, and the phase structure was obtained on atransmission electron microscope photograph. The results are shown inTable 6. In each of the stretched samples, the wavelength ofconcentration fluctuation was longer than that before stretching, and itcan be considered that coarsening occurred during stretching.Furthermore, from each of the films stretched to 2 times, a 50 mm long,10 mm wide and 0.03 mm sample was cut out, and from each of the filmsstretched to 4 times, a 50 mm long, 10 mm wide and 0.01 mm thick samplewas cut out. The tensile strength and tensile elongation of each samplewas measured at an inter-chuck distance of 20 mm and at a tensile speedof 10 mm/min. The results are shown in Table 6.

COMPARATIVE EXAMPLE 9

[0216] Melt blending was carried out as described for Working Example21, except that a single-screw extruder (40 mm diameter) having afull-flighted screw was used at a screw rotated speed of 50 rpm. The gutdischarged from the die was immediately quickly cooled in icy water, toobtain a gut with its structure fixed. The gut was cloudy. The phasestructure of the gut was observed with a transmission electronmicroscope, and heterogeneously dispersed structure of 0.5 μm and morewere observed. From the result, it can be seen that the gut was of asystem not made miscible under the shear flow in the extruder. Also fromthis system, a film was produced as described for Working Example 21,and the mechanical properties were measured. The results are shown inTable 6. Furthermore, from this film, a 100 mm square sample was cutout, fastened using clips on its four sides, preheated at 90° C. for 60seconds, and simultaneously biaxially stretched at a stretching speed of2000%/min at a stretching ratio or 2 times or 4 times in an oven kept at90° C. However, it was broken at a clip portion and did not allowstretching.

[0217] From the results of Working Examples 19 to 23 and ComparativeExample 9, it can be seen that films having a co-continuous structurewith a specific wavelength of concentration fluctuation or a dispersedstructure formed by the spinodal decomposition of this invention, andthe films obtained by stretching the films have excellent strength andtoughness. TABLE 6 Working Working Working Example 19 Example 20 Example21 Composition PC-1 (wt %) 90 70 50 PBT-1 (wt %) 10 30 50 Extruded gutPolymer alloy Miscible Miscible Miscible structure (transparent)(transparent) (transparent) Film Polymer alloy Dispersed Co-continuousCo-continuous structure structure structure structure (transparent)(transparent) (transparent) Wavelength of (μm) 0.003 0.003 0.003concentration fluctuation or distance between particles Tensile strength(MPa) 96 95 90 Tensile elongation (%) 210 290 350 Stretched film Polymeralloy Dispersed Co-continuous Co-continuous (lengthwise 2 times ×crosswise structure structure structure structure 2 times) (transparent)(transparent) (transparent) Wavelength of (μm) 0.008 0.008 0.008concentration fluctuation or distance between particles Mechanicalproperties Tensile strength (MPa) 97 105 97 Tensile elongation (%) 180230 250 Stretched film Polymer alloy Dispersed Co-continuousCo-continuous (lengthwise 4 times × crosswise structure structurestructure structure 4 times) (transparent) (transparent) (transparent)Wavelength of (μm) 0.015 0.015 0.016 concentration fluctuation ordistance between particles Mechanical properties Tensile strength (MPa)100 108 106 Tensile elongation (%) 150 200 220 Working WorkingComparative Example 22 Example 23 Example 9 Composition PC-1 (wt %) 3010 50 PBT-1 (wt %) 70 90 50 Extruded gut Polymer alloy Miscible MiscibleImmiscible structure (transparent) (transparent) (cloudy) Film Polymeralloy Co-continuous Dispersed Dispersed structure structure structurestructure (transparent) (transparent) (cloudy) Wavelength of (μm) 0.0030.003 — concentration fluctuation or distance between particles Tensilestrength (MPa) 86 75 58 Tensile elongation (%) 410 420 45 Stretched filmPolymer alloy Co-continuous Dispersed Stretching not (lengthwise 2 times× crosswise structure structure structure allowed 2 times) (transparent)(transparent) Wavelength of (μm) 0.008 0.008 — concentration fluctuationor distance between particles Mechanical properties Tensile strength(MPa) 91 79 — Tensile elongation (%) 275 310 — Stretched film Polymeralloy Co-continuous Dispersed Stretching not (lengthwise 4 times ×crosswise structure structure structure allowed 4 times) (transparent)(transparent) Wavelength of (μm) 0.016 0.015 — concentration fluctuationor distance between particles Mechanical properties Tensile strength(MPa) 95 83 — Tensile elongation (%) 240 250 —

WORKING EXAMPLES 24 and 25

[0218] Raw materials with a composition ratio shown in Table 7 were fedinto a twin-screw extruder (PCM-30 produced by Ikegai Kogyo) set at anextrusion temperature of 240° C., having two kneading zones and revolvedat a high screw rotated speed of 300 rpm. The gut discharged from thedie was immediately quickly cooled in icy water, to fix its structure.Both the guts were transparent. The phase structures of the guts wereobserved with a transmission electron microscope, and it was confirmedthat neither of the samples had structure of 0.001 μm or more, and thatboth the samples were made miscible. From the results, it can be seenthat this series was made miscible under the shear flow of an extruderset an extrusion temperature of 240° C.

[0219] This series was of a system with an LCST type phase diagram, andhad the miscible region expanded under the shear flow of an extruder.

[0220] Furthermore, each of the guts was pelletized into pellets using astrand cutter. The pellets were fed into a single-screw extruder (30 mmdiameter) set at an extrusion temperature of 250° C. and having a T dieat the tip, to produce a film. For producing the film, a casting drummade of hard chromium and having a mirror finished surface with thetemperature kept at 20° C. was placed right under (3 cm) the T die. Theresin discharged from the mouthpiece of the T die was cast onto thecasting drum, and static electricity of 8 kV was applied to bring thefilm into contact with the casting drum, for quickly cooling it, to fixthe structure. Furthermore, the film was passed between rolls set at 5m/min to keep the take-up speed constant, and taken up using a take-uproll, to obtain a film. The thickness of each of the obtained films was0.5 mm. The obtained films were transparent. The phase structures of thefilms were observed with a transmission electron microscope, and it wasconfirmed that each sample had a co-continuous structure or a dispersedstructure. From the obtained films, further samples were cut out formeasurement using small-angle X-ray scattering. With each sample, a peakwas observed. Table 6 shows the wavelengths of concentration fluctuation(Λm) calculated from the peak positions (θm).

[0221] From the above results, it can be considered that when a film isformed, a miscible state is kept even under the shear flow in asingle-screw extruder, that after discharge from a T die, the spinodaldecomposition under no shear flow causes phase separation, and that thesubsequent quick cooling causes the structure to be fixed.

[0222] Subsequently, from the films, 85 mm long, 20 mm wide and 0.5 mmthick strip samples were cut out. Each specimen was held at one endportion of 20 mm and fastened to be horizontal like a cantilever. Thespecimens were placed in an oven of 100, 110, 120, 130, 140, 150 or 160°C. for 60 minutes, and for each specimen, the vertical distance of thetip opposite to the held portion, hanging down by its own weight wasmeasured. The relation between the hanging-down vertical distance ateach temperature and the temperature was plotted, and the temperatureintersecting with a hanging-down vertical distance of 3 mm wasidentified as the heat resistance temperature. The value is shown inTable 7.

COMPARATIVE EXAMPLE 10

[0223] Melt blending was carried out as described for Working Example25, except that a single-screw extruder (40 mm diameter) having afull-flighted screw was used at a screw rotated speed of 50 rpm. The gutdischarged from the die was immediately quickly cooled in icy water, toobtain a gut with its structure fixed. The gut was cloudy. The phasestructure of the gut was observed with a transmission electronmicroscope, and heterogeneously dispersed structure of 0.5 μm and morewere observed. From the result, it can be seen that the sample was of asystem not made miscible under the shear flow in the extruder. Also fromthis sample, a film was produced as described for Working Example 25,and heat resistance was measured. The result is shown in Table 7.

[0224] From the results of Working Examples 24 and 25 and ComparativeExample 10, it can be seen that films having a co-continuous structurewith a specific wavelength of concentration fluctuation or a dispersedstructure formed by the spinodal decomposition of this invention haveexcellent heat resistance. TABLE 7 Working Working Comparative Example24 Example 25 Example 10 Composition PC-1 (wt %) 90 70 70 AS-1 (wt %) 1030 30 Extruded gut Polymer alloy Miscible Miscible Immiscible structure(transparent) (transparent) (cloudy) Film Polymer alloy DispersedCo-continuous Dispersed structure structure structure structure(transparent) (transparent) (cloudy) Wavelength of (μm) 0.008 0.008 —concentration fluctuation or distance between particles Heat resistance(° C.) 147 145 120

[0225] As described above, the polymer alloy film of this invention hassuch properties as excellent strength and toughness or excellent heatresistance, depending on the resins used in combination. The film havingexcellent strength and toughness can be usefully used as a filmespecially requiring moldability. Furthermore, the polymer alloy film ofthis invention has also a property of excellent regularity, and can alsobe usefully used as a functional film based on it.

[0226] In the following Working Examples 26 to 32 and ComparativeExamples 11 to 14, the following evaluation methods were used.

[0227] (1) Mold Shrinkage Factor

[0228] Eighty-millimeter square plates with a thickness of 1 mm (filmgates) were produced by molding at a mold temperature of 80° C. inmolding cycles consisting of 10 seconds of follow-up pressureapplication and 10 seconds of cooling. The dimensions of the obtainedsquare plates in the resin flow direction (machine direction) and in thedirection perpendicular to the resin flow (transverse direction) wererespectively measured, and the shrinkage factors to the dimension of themold were obtained.

[0229] (2) Heat Shrinkage Factor

[0230] The 80 mm square plates with a thickness of 1 mm obtained in theabove were heat-treated in a hot air oven kept at 60° C. for 2 hours.The dimensions of the heat-treated square plates in the machinedirection and in the transverse direction were measured, and theshrinkage factors to the dimensions of the square plates not yetheat-treated were obtained.

[0231] (3) Overall Shrinkage Factor

[0232] This was calculated as the sum of the mold shrinkage factor andthe heat shrinkage factor.

WORKING EXAMPLES 26 to 32

[0233] Raw materials with a composition ratio shown in Table 8 were fedinto a twin-screw extruder (PCM-30 produced by Ikegai Kogyo) set at anextrusion temperature of 260° C., with its screws arranged to have twokneading zones and with the screw rotated speed set at 100 rpm as shownin Table 8. The gut discharged from the die was passed through a coolingbath filled with 100 liters of 20° C. water taking 15 seconds, for beingquickly cooled to fix the structure. All the guts were transparent, andthe phase structures of the guts were observed with a transmissionelectron microscope. It was confirmed that none of the samples hadstructure of 0.001 μm or more, and that they were made miscible. Fromthe results, it can be seen that this series could be made miscible inan extruder with an extrusion temperature of 260° C. Furthermore, theglass transition temperatures of 10 mg samples cut out of the guts weremeasured using DSC, and the results are shown in Table 8.

[0234] This series was of a system with an LCST type phase diagram, andhad the miscible region expanded under the shear flow of an extruder toallow making miscible.

[0235] Furthermore, from the guts, 100 μm thick sections were cut outand respectively heat-treated at 260° C., and the structure-formingprocesses during the heat treatment were traced using small-angle X-rayscattering and light scattering. With every sample, a peak appeared 0.5minute after start of heat treatment, and furthermore, when the peak wasobserved, a tendency of strength increase was observed without anychange in the peak position. The stage in which the strength increaseswithout any change in the peak position in the small-angle X-rayscattering and light scattering corresponds to the early stage ofspinodal decomposition. The phase structures were observed as describedfor Working Example 1, and the results are shown in Table 8.

[0236] The sections measured using small-angle X-ray scattering andlight scattering had structures formed in the early stage, andsubsequently continuously heat-treated at the above-mentionedtemperature for 2 minutes in total. The wavelengths of concentrationfluctuation were measured using small-angle X-ray scattering and lightscattering, and the phase structures were observed on transmissionelectron microscope photographs. The results are shown in Table 8.

[0237] Moreover, the guts were pelletized using a pelletizer intopellets to be injection-molded. The obtained pellets wereinjection-molded using an injection molding machine (PS-60E9DSE)produced by Nissei Plastic Industrial Co., Ltd. set at 240° C., 250° C.,260° C. and 260° C. from the hopper bottom toward the tip, at a moldtemperature of 80° C. in molding cycles consisting of 10 seconds offollow-up pressure application and 10 seconds of cooling, to produce 80mm square plates with a thickness of 1 mm.

[0238] From the obtained square plates, 100 μm thick sections were cutout, and as with the samples cut out of the guts, the wavelengths ofconcentration fluctuation or the distances between particles wereobtained using small-angle X-ray scattering and light scattering, andthe phase structures were observed on transmission electron microscopephotographs. The results are shown in Table 8. From the results, it canbe seen that even injection molding allowed the formation of structuressimilar to those formed when the samples cut out of the guts wereheat-treated.

[0239] As the flowability indicating injection moldability, the lowestinjection pressure for filling the aforesaid 80 mm square mold with athickness of 1 mm with the resin composition up to its tip was obtained,and it is shown in Table 8 as the lowest molding pressure. Furthermore,the specific gravity of each injection-molded article was obtained by anunderwater replacement method using the aforesaid square plate.

[0240] As can be seen from the comparison between Working Examples 28and 29, if the shear flow during melt blending is intensified, a finerstructure can be formed, and a molded article with more excellentinjection moldability and dimensional stability can be obtained. TABLE 8Working Example Working Example Working Example Working Example 26 27 2829 Composition PBT-2 parts by 100 100 100 100 weight PC-2 parts by 11 2543 43 weight PC-3 parts by weight E-1 parts by 0.1 0.1 0.1 0.1 weightReleasing agent parts by 0.4 0.4 0.4 0.4 weight Extrusion Screw speed(rpm) 300 300 300 100 condition Melt blending Melt blending Meltblending Ordinary melt under strong under strong under strong blendingshear shear shear Extruded gut Miscibility Miscible Miscible MiscibleMiscible Glass transition (° C.) 49 (single) 58 (single) 69 (single) 69(single) temperature Extruded gut Heat treatment 260° C. × 0.5 min 260°C. × 0.5 min 260° C. × 0.5 min 260° C. × 0.5 min (heat-treated)conditions Initial structure Co-continuous Co-continuous Co-continuousCo-continuous structure structure structure structure Wavelength of (μm)0.01 0.02 0.02 0.08 concentration fluctuation Heat treatment 260° C. × 2min 260° C. × 2 min 260° C. × 2 min 260° C. × 2 min conditions Polymeralloy Dispersed Co-continuous Co-continuous Co-continuous structurestructure structure structure structure Wavelength of (μm) 0.13 0.080.06 0.12 concentration fluctuation or distance between particlesStructural mode Spinodal Spinodal Spinodal Spinodal decompositiondecomposition decomposition decomposition Injection-molded Polymer alloyDispersed Co-continuous Co-continuous Co-continuous article structurestructure structure structure structure Wavelength of (μm) 0.15 0.090.06 0.13 concentration fluctuation or distance between particlesSpecific gravity 1.29 1.28 1.26 1.26 Flowability Lowest molding (MPa) 3235 39 45 pressure (square plate) Mold shrinkage Machine direction (1 mm(%) 0.95 0.71 0.58 0.89 factor thick) Traverse direction (1 mm (%) 0.980.88 0.77 0.91 thick) Heat shrinkage Machine direction (1 mm (%) 0.080.07 0.06 0.08 factor (60° C. × thick) 2 hours) Traverse direction (1 mm(%) 0.08 0.07 0.05 0.07 thick) Overall Machine direction (1 mm (%) 1.030.78 0.64 0.97 shrinkage factor thick) (60° C. × Traverse direction (1mm (%) 1.06 0.95 0.82 0.98 2 hours) thick) Working Example WorkingExample Working Example 30 31 32 Composition PBT-2 (wt %) 100 100 100PC-2 (wt %) 90 110 PC-3 (wt %) 43 E-1 (wt %) 0.1 0.1 0.1 Releasing agent(wt %) 0.4 0.4 0.4 Extrusion Screw speed (rpm) 300 300 300 conditionMelt blending Melt blending Melt blending under strong under strongunder strong shear shear shear Extruded gut Miscibility MiscibleMiscible Miscible Glass transition (° C.) 67 (single) 92 (single) 102(single) temperature Extruded gut Heat treatment 260° C. × 0.5 min 260°C. × 0.5 min 260° C. × 0.5 min (heat-treated) condition Initialstructure Co-continuous Co-continuous Co-continuous structure structurestructure Wavelength of (μm) 0.02 0.01 0.02 concentration fluctuationHeat treatment 260° C. × 2 min 260° C. × 2 min 260° C. × 2 minconditions Polymer alloy Dispersed Co-continuous Co-continuous structurestructure structure structure Wavelength of (μm) 0.04 0.05 0.06concentration fluctuation or distance between particles Structural modeSpinodal Spinodal Spinodal decomposition decomposition decompositionInjection-molded Polymer alloy Dispersed Dispersed Co-continuous articlestructure structure structure structure Wavelength of (μm) 0.05 0.050.06 concentration fluctuation or distance between particles Specificgravity 1.26 1.25 1.25 Flowability Lowest molding (MPa) 48 59 75pressure (square plate) Mold shrinkage Machine direction (1 mm (%) 0.580.43 0.37 factor thick) Traverse direction (1 mm (%) 0.72 0.56 0.41thick) Heat shrinkage Machine direction (1 mm (%) 0.06 0.02 0.02 factor(60° C. × thick) 2 hours) Traverse direction (1 mm (%) 0.05 0.02 0.02thick) Overall Machine direction (1 mm (%) 0.64 0.45 0.39 shrinkagefactor thick) (60° C. × Traverse direction (1 mm (%) 0.82 0.58 0.43 2hours) thick)

COMPARATIVE EXAMPLE 11

[0241] Raw materials were melt blended and pelletized, and the pelletswere injection-molded as described for Working Example 26, except thatPBT only was used as a resin. Also for this sample, injectionmoldability and dimensional stability were measured as described forWorking Example 26. As a result, only a molded article with poordimensional stability could be obtained, even though it was excellent ininjection moldability. The results are shown in Table 9.

COMPARATIVE EXAMPLE 12

[0242] Melt blending, pelletization and injection molding were carriedout as described for Working Example 28, except that a single-screwextruder (Tanabe VS40-32) set at a screw rotated speed of 100 rpm wasused for melt blending. Also for this sample, injection moldability anddimensional stability were measured as described for Working Example 26,and only a molded article with poor dimensional stability could beobtained. The results are shown in Table 9.

COMPARATIVE EXAMPLE 13

[0243] Melt blending, pelletization and injection molding were carriedout as described for Working Example 26, except that 27 parts by weightof PC and 6. 7 parts by weight of styrene-containing acrylic graftcopolymer were mixed with 100 parts by weight of PBT and that the screwrotated speed was set at 100 rpm as set for general melt blending. Theextruded gut was also observed as described for Working Example 1, and astructure separated into two phases was observed. Furthermore, when theglass transition temperature of a 10 mg sample cut out of the gut wasmeasured using DSC, two glass transition temperatures attributable tothe two phases were measured contrary to the fact that a single glasstransition temperature was measured as a feature of the miscible systemsobtained in Working Examples 26 to 32. From the results, it can be seenthat this system was immiscible during melt blending. Next, thestructure of the extruded gut during heat treatment was observed asdescribed for Working Example 26, and as a result, in light scattering,no peak appeared. Furthermore, the transmission electron microscopephotograph showed a structure in which two separated phases aredispersed like an irregular network. Also for this sample, injectionmoldability and dimensional stability were measured as described forWorking Example 26, and as a result, only a molded article with poordimensional stability could be obtained, though it had excellentinjection moldability. The results are shown in Table 9.

COMPARATIVE EXAMPLE 14

[0244] Melt blending, pelletization and injection molding were carriedout as described for Working Example 26, except that PC only was used asa resin. Also for this sample, injection moldability and dimensionalstability were measured as described for Working Example 26, and as aresult, only a molded article very low in the flowability indicatinginjection moldability could be obtained, though it had excellentdimensional stability.

[0245] The results are shown in Table 9. TABLE 9 Comparative ComparativeComparative Comparative Example 11 Example 12 Example 13 Example 14Composition PBT-2 parts by 100 100 100 weight PC-2 parts by 43 27 100weight E-1 parts by 0.1 weight X-1 parts by 6.7 weight Releasing agentparts by 0.4 0.4 0.4 0.4 weight Extrusion Screw speed (rpm) 300 100 100300 condition Melt blending Single-screw Ordinary melt Melt blendingunder strong melt-blending blending under strong shear shear Extrudedgut Miscibility — Immiscible Immiscible — Glass transition (° C.) 32 33,150 33, 150 151 temperature Extruded gut Heat treatment — 260° C. × 0.5min 260° C. × 0.5 min — (heat-treated) conditions Initial structure —Dispersed Network — structure structure Wavelength of (μm) — 1.8 Withoutco- — concentration continuous fluctuation structure Heat treatment —260° C. × 2 min 260° C. × 2 min — conditions Polymer alloy structure —Dispersed Network — structure structure Wavelength of (μm) — 1.8 Withoutco- — concentration continuous fluctuation or distance structure betweenparticles Structural mode — Irregularly Irregular network — dispersedInjection-molded Polymer alloy structure — Dispersed Network — articlestructure structure Wavelength of (μm) — 1.8 Without co- — concentrationcontinuous fluctuation or distance structure between particles Specificgravity 1.31 1.26 1.27 1.20 Flowability Lowest molding (MPa) 35 42 52 87pressure (square plate) Mold shrinkage Machine direction (1 mm (%) 1.391.21 1.15 0.49 factor thick) Traverse direction (1 mm (%) 1.45 1.23 1.280.53 thick) Heat shrinkage Machine direction (1 mm (%) 0.17 0.14 0.130.01 factor (60° C. × 2 hours) thick Traverse direction (1 mm (%) 0.180.15 0.14 0.02 thick) Overall shrinkage Machine direction (1 mm (%) 1.561.35 1.28 0.50 factor (60° C. × 2 hours) thick) Traverse direction (1 mm(%) 1.63 1.38 1.42 0.55 thick)

[0246] From the results of Working Examples 26 to 32 and ComparativeExamples 11 to 14, it can be seen that samples structurally controlledto have a co-continuous structure with a wavelength of concentration offluctuation of 0.01 to 1 μm or a dispersed structure with a distancebetween particles of 0.01 to 1 μm by melt blending the polymer alloys ofthis invention are decreased in the mold shrinkage factors at the timeof injection molding and in the heat shrinkage factors after heattreatment and also excellent in moldability.

WORKING EXAMPLES 33 to 41

[0247] Raw materials with a composition ratio shown in Table 10 were fedinto a parallel plates type shear flow-applying device (CSS-430 producedby Linekam), and molten at a kneading temperature of 320° C. Then, ashear field was applied at the shear rate shown in Table 10. Everysample was observed in the portion subjected to the shear field at theshear rate shown in Table 10, and it was confirmed that none of thesamples have any structure. Each sample was immediately quickly cooledin icy water to obtain a sample its structure fixed. The phase structureof the obtained sample was observed with a transmission electronmicroscope. It was confirmed that none of the samples had structure of0.001 μm or more, and that they were made miscible. So, it was foundthat this series could be made miscible at 320° C. under the shearingcondition shown in Table 10.

[0248] Next, raw materials with a composition ratio shown in Table 10were fed into a twin-screw extruder (PCM-30 produced by Ikegai Kogyo)set at an extrusion temperature of 320° C., having two kneading zonesand revolved at a high screw rotated speed of 300 rpm, and the gutdischarged from the die was immediately quickly cooled in icy water, tofix the structure. All the guts were transparent. The phase structuresof the guts were observed with a transmission electron microscope, andit was confirmed that none of the samples had structure of 0.001 μm ormore, and that they were made miscible. So, it can be seen that thisseries could be made miscible under the shear flow in an extruder set atan extrusion temperature of 320° C.

[0249] Then, each of the guts was heat-treated using a hot press at thetemperature shown in Table 10 and for the time period shown in Table 10,and quickly cooled to produce a sheet (0.2 mm thick) with its structurefixed. From the sheet, a 100 μm thick section was cut out, and wasmeasured using small-angle X-ray scattering or light scattering. Table10 shows the wavelengths of concentration fluctuation (Λm) calculatedfrom the peak position (θm).

[0250] From the above, it can be considered that a sample made miscibleunder the shear flow of a twin-screw extruder was separated into phasesowing to the spinodal decomposition when it was formed into a sheetusing a hot press, and that when it was subsequently quickly cooled, thestructure was fixed.

[0251] Subsequently from each of the sheets, a 50 mm long, 10 mm wideand 0.2 mm thick sample was cut out. The tensile strength was measuredat an inter-chuck distance of 20 mm and a tensile speed of 10 mm/min,and after it was allowed to stand in a hot air oven kept at 180° C. for30 minutes, its heat shrinkage factor (%) in reference to the initiallength was measured. The results are shown in Table 10.

COMPARATIVE EXAMPLE 15

[0252] The tensile strength and heat shrinkage factor of a sample weremeasured as described for Working Example 35, except that the heattreatment was carried out at 320° C. for 3 minutes, and the phasestructure was observed. The results are shown in Table 10.

[0253] When the heat treatment temperature was high as in this examplecausing the structure to be coarsened, hence causing the wavelength ofconcentration fluctuation to exceed the scope of the present invention,then only a sample poor in mechanical properties and heat resistancecould be obtained.

COMPARATIVE EXAMPLE 16

[0254] Raw materials were melt blended as described for Working Example35, except that polybutylene terephthalate resin was used as an alloycomponent in addition to PPS resin, and a gut was discharged from thedie and quickly cooled in icy water, to obtain a gut with its structurefixed. This sample was cloudy. The phase structure of the gut wasobserved with a transmission electron microscope. Heterogeneouslydispersed structure of 2.0 μm and more were observed. From the result,it can be seen that the sample was made miscible under the shear flow inan extruder with an extrusion temperature of 320° C. Also for thissample, the tensile strength and heat shrinkage factor were measured asdescribed for Working Example 35, and the structure was observed. Theresults are shown in Table 10. TABLE 10 Working Working Working WorkingExample 33 Example 34 Example 35 Example 36 Composition PPS-1 (wt %) 9080 70 70 PET-1 (wt %) 10 20 30 30 PBT-3 (wt %) Kneading Shear rate(sec⁻¹) 1000 1000 1000 1000 conditions Miscibility Miscible MiscibleMiscible Miscible Extruded gut Polymer alloy Miscible Miscible MiscibleMiscible structure (transparent) (transparent) (transparent)(transparent) Sheet (heat- Heat treatment 290° C. × 1 min 290° C. × 1min 290° C. × 1 min 290° C. × 2 min treated) conditions Polymer alloyDispersed Co-continuous Co-continuous Co-continuous structure structurestructure structure structure Wavelength of (μm) 0.03 0.3 0.7 1.1concentration fluctuation or distance between particles Tensile strength(MPa) 88 82 78 73 Heat shrinkage factor (%) 0.1 0.3 0.4 0.7 WorkingWorking Working Working Example 37 Example 38 Example 39 Example 40Composition PPS-1 (wt %) 70 60 50 30 PET-1 (wt %) 30 40 50 70 PBT-3 (wt%) Kneading Shear rate (sec⁻¹) 1000 1000 1000 1000 conditionsMiscibility Miscible Miscible Miscible Miscible Extruded gut Polymeralloy Miscible Miscible Miscible Miscible structure (transparent)(transparent) (transparent) (transparent) Sheet (heat- Heat treatment290° C. × 3 min 290° C. × 1 min 290° C. × 1 min 290° C. × 1 min treated)conditions Polymer alloy Co-continuous Co-continuous Co-continuousCo-continuous structure structure structure structure structureWavelength of (μm) 1.5 1.1 1.0 0.8 concentration fluctuation or distancebetween particles Tensile strength (MPa) 64 70 68 65 Heat shrinkagefactor (%) 1.2 0.7 0.9 1.1 Working Comparative Comparative Example 41Example 15 Example 16 Composition PPS-1 (wt %) 10 70 70 PET-1 (wt %) 9030 PBT-3 (wt %) 30 Kneading Shear rate (sec⁻¹) 1000 — — conditionsMiscibility Miscible — — Extruded gut Polymer alloy Miscible MiscibleImmiscible structure (transparent) (transparent) (cloudy) Sheet (heat-Heat treatment 290° C. × 1 min 320° C. × 3 min 290° C. × 1 min treated)conditions Polymer alloy Dispersed Dispersed Dispersed structurestructure structure structure Wavelength of (μm) 0.03 2.2 —concentration fluctuation or distance between particles Tensile strength(MPa) 63 54 43 Heat shrinkage factor (%) 1.5 3.0 5.1

[0255] From the results of Working Examples 33 and 41 and ComparativeExamples 15 and 16, it can be seen that the co-continuous structure witha specific wavelength of concentration fluctuation or dispersedstructure, respectively consisting of PPS resin and PET resin, of thisinvention have excellent mechanical properties and heat resistance.

[0256] The polymer alloy of this invention, containing polyphenylenesulfide resin and a polyester resin with polyethylene terephthalate as amain component and having a specific structure, can be a polymer alloyhaving the excellent properties of the polyphenylene sulfide resin.

[0257] The manufacturing method as the first version of this inventioncan provide a polymer alloy having excellent regularity and having ahomogeneously dispersed fine structure. The obtained polymer alloy isexcellent in such properties as strength, toughness and heat resistance,depending on the resins used in combination, and can be usefully used asa structural material based on these properties. Furthermore, thepolymer alloy obtained according to this invention can also be usefullyused as a function material based on its excellent regularity.

[0258] The polymer alloy pellets as the second or third version of thisinvention can be used to produce a molded article, film, fibers or thelike with excellent mechanical properties at high productivity.Especially the polymer alloy, polymer alloy film or sheet, moldedpolymer alloy article and the like as the fourth to seventh versions ofthis invention can be suitably produced.

[0259] The polymer alloy film or sheet as the fourth version of thisinvention has excellent properties such as strength, toughness and heatresistance, depending on the resins used in combination, and can beespecially usefully used as a film requiring moldability. Moreover, thepolymer alloy film or sheet of this invention has also a property ofexcellent regularity, and can also be usefully used as a functional filmor sheet based on the regularity.

[0260] Furthermore, the polymer alloy film obtained according to thisinvention can be used in various methods, generally depending on thefeature of its components. Above all, it can be suitably used as amoldable film enhanced in toughness by using a resin with excellentmechanical properties as one of the resins, or as a heat-resistant filmenhanced in heat resistance by using a resin with excellent heatresistance as one of the resins, or as a functional film in which afunctional component loaded with a magnetic substance, a catalyst or thelike is finely dispersed in one of the resins. Moreover, the polymeralloy film can also be suitably used as a transparent film based on thestructural control of this invention capable of achieving a wavelengthshorter than that of visible light.

[0261] The moldable film can be, for example, suitably used as anin-mold film, transfer foil or a film for various packages, etc.

[0262] The molded polymer alloy article as the fifth version of thisinvention and the polymer alloy as the sixth version are, in view ofproperties, decreased in the mold shrinkage factor during molding and inthe heat shrinkage factor after heat treatment, excellent also inmoldability, and low in specific gravity. Based on these properties,they can be usefully used for such applications as electric andelectronic apparatus parts, automobile parts, and mechanical systemparts.

[0263] The polymer alloy as the seventh version of this invention hasexcellent heat resistance and chemicals resistance of polyphenylenesulfide and is also economically excellent. So, it can be suitably usedfor various film applications and also for such applications as bagfilter, motor-binding string, motor-binding tape, dryer canvas forpapermaking, net conveyor for thermal bond method or thermal bondprocess of nonwoven fabric, carrier belt in a drying machine or heattreatment machine, filter, etc. Especially in the case where it isprocessed into fibers, fibers with excellent properties can be obtained.

1. A method for manufacturing a polymer alloy, comprising the step ofmelt blending at least two resins used as components miscible under suchshear flow as caused by the shear rate kept in a range from 100 to 10000sec⁻¹ and capable of being separated into phases under no shear flow,for making the resins miscible and subsequently inducing spinodaldecomposition to cause phase separation, for forming a co-continuousstructure with a wavelength of concentration fluctuation of 0.001 to 1μm or a dispersed structure with a distance between particles of 0.001to 1 μm.
 2. A method for manufacturing a polymer alloy, according toclaim 1, wherein in the early stage of said spinodal decomposition, aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 1 μm is formed.
 3. Polymer alloy pellets, comprising atleast two resins contained as components immiscible under no shear flow,wherein the said at least two resins contained as components are mademiscible.
 4. Polymer alloy pellets, according to claim 3, wherein saidat least two resins contained as components are a thermoplasticpolyester resin and a polycarbonate.
 5. Polymer alloy pellets, accordingto claim 4, wherein said thermoplastic polyester resin is polybutyleneterephthalate.
 6. Polymer alloy pellets, comprising at least two resinscontained as components, wherein the at least two resins contained ascomponents form a co-continuous structure with a wavelength ofconcentration fluctuation of 0.001 to 1 μm or a dispersed structure witha distance between particles of 0.001 to 1 μm.
 7. Polymer alloy pellets,according to claim 6, wherein said at least two resins are athermoplastic polyester resin and a polycarbonate.
 8. Polymer alloypellets, according to claim 7, wherein said thermoplastic polyesterresin is polybutylene terephthalate.
 9. A polymer alloy film or sheet,comprising at least two resins contained as components, wherein the atleast two resins contained as components form a co-continuous structurewith a wavelength of concentration fluctuation of 0.001 to 1 μm or adispersed structure with a distance between particles of 0.001 to 1 μm.10. A polymer alloy film or sheet, according to claim 9, wherein aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to less than 0.01 μm or a dispersed structure with a distancebetween particles of 0.001 to less than 0.01 μm is formed.
 11. A polymeralloy film or sheet, according to claim 10, wherein said co-continuousstructure or dispersed structure is formed by the phase separationcaused by the spinodal decomposition induced in the at least two resinscontained as components.
 12. A polymer alloy film or sheet, according toclaim 9, wherein said at least two resins contained as components arepolybutylene terephthalate and a polycarbonate.
 13. A molded polymeralloy article, comprising at least two resins contained as components,wherein the at least two resins contained as components form aco-continuous structure with a wavelength of concentration fluctuationof 0.001 to 1 μm or a dispersed structure with a distance betweenparticles of 0.001 to 1 μm.
 14. A molded polymer alloy article,according to claim 13, wherein said molded polymer alloy article is amolded article obtained by injection molding.
 15. A molded polymer alloyarticle, according to claim 13, wherein said at least two resinscontained as components are polybutylene terephthalate and apolycarbonate.
 16. A polymer alloy, comprising polybutyleneterephthalate and a polycarbonate, and forming a co-continuous structurewith a wavelength of concentration fluctuation of 0.001 to 1 μm or adispersed structure with a distance between particles of 0.001 to 1 μm.17. A polymer alloy, according to claim 16, wherein said co-continuousstructure or dispersed structure is formed by the phase separationcaused by the spinodal decomposition.
 18. A polymer alloy, according toclaim 16, wherein said polymer alloy is miscible when the shear rate iskept in a range from 100 to 10000 sec⁻¹, and is separated into phasesunder no shear flow.
 19. A polymer alloy, comprising polyphenylenesulfide resin and a polyester resin with polyethylene terephthalate as amain component, and forming a co-continuous structure with a wavelengthof concentration fluctuation of 0.001 to 2 μm or a dispersed structurewith a distance between particles of 0.001 to 2 μm.
 20. A polymer alloy,according to claim 19, wherein said co-continuous structure or dispersedstructure is formed by the phase separation caused by the spinodaldecomposition.
 21. A polymer alloy, according to claim 20, wherein saidpolymer alloy is miscible when the shear rate is kept in a range from100 to 10000 sec⁻¹, and is separated into phases under no shear flow.